Nutty Butter Layer Cake
E
By Emma
Certified Culinary Professional
•
Recipe tested & approved
Brown butter transforms the cake base, lending a deep toasted note. Cake pans prepped with shortening, parchment, and flour create layers with clean release. Gelatin and coffee liqueur give mousse a rich, slightly boozy complexity, folded with whipped cream for airiness. Alternate beating and folding keep textures distinct yet harmonized. Baking at a low temp ensures gentle rise and moist crumb. The buttercream frosting seals flavors and holds the assembled layers together. Timing cues rely on color, smell, and texture rather than clocks alone. Each element handled with purpose, few shortcuts. Twist in cake flour for lighter bite. Simple swaps easily accommodate pantry staples.
Prep:
20 min
Cook:
42 min
Total:
62 min
Servings:
12 servings
#American desserts
#layer cakes
#chocolate mousse
#brown butter
#baking techniques
Brown butter makes a world of difference. That nutty deep aroma fills the kitchen, and you catch the moment it hits amber. Beat it right after cooling and it holds air like crazy. I swapped 5% flour for cake flour once—lighter texture, less dense. Mousse with gelatin keeps shape without gel-like stiffness. Coffee liqueur adds warmth, not overpowering. Folding whipped cream carefully preserves fluff, so mousse stays airy but stable. Baking low and slow, rotating pans midway, watching color not clock. Cool partially in pans to keep moist crumb, but no soggy mess. Crisp edges, rich layers stacked with mousse between. Buttercream ties it all up, smooth but not slippery. Tried no gelatin once—mousse sad for hours. Learned patience with chilling times, texture cues beat measurements here.
Ingredients
- 2 sticks unsalted butter
- 2 1/8 cups all-purpose flour
- 1 tablespoon baking powder
- 1 teaspoon fine sea salt
- 1 1/4 cups granulated sugar
- 1 tablespoon vanilla extract
- 3 large eggs plus 2 egg yolks
- 3/4 cup whole milk
- Vegetable shortening for pans
- Gelatin powder 1 tablespoon
- 3 tablespoons cold water
- 1 cup heavy cream
- 2 tablespoons coffee liqueur
- 1/3 cup granulated sugar (for mousse)
- 1/8 teaspoon salt (for mousse)
- 5 oz bittersweet chocolate, melted
- Powdered sugar for dusting
About the ingredients
Brown butter is key—don’t rush the low heat watch. Butter is your flavor base so choose unsalted, quality brand. Flour swap: using mostly cake flour softens crumb but keep a bit of all-purpose for structure. Vanilla extract really boosts the sugar step, adds depth. Whole eggs plus extra yolks bring richness needed to balance flour’s dryness. Milk temp is room temp for even batter texture; cold milk toughens gluten. Gelatin must soften fully—you can test by pressing between fingers to check for lumps. Heavy cream cold before whipping holds peaks better, beat to soft peaks—don’t overwhip or mousse gets grainy. Coffee liqueur can be swapped with concentrate or espresso powder but liquid form helps dissolve gelatin better. Sugar for mousse is less than cake to keep balance. Pans prepped precisely: shortening then parchment prevents stuck cakes while dusting flour keeps mess minimal. Buttercream should be smooth, not oily—palmer method preferred by some cooks but a basic American-style is enough here. Keep powdered sugar handy for dusting—gives visual pop.
Method
Cake
- Heat oven to 320°F. Grease two 8 inch round pans with shortening. Line bottom with parchment. Dust with flour, tap out excess. Keeps layers even, cakes clean to remove.
- Melt butter slowly in saucepan over low heat. Stir often, watch milk solids shift from white specks to golden brown, smell shifts to toasted nuts. About 12 minutes here, not exact. Scrape butter plus browned bits into large heatproof bowl.
- Set bowl in ice water bath to chill edges now. Butter softens but begins firming around outside, roughly 7 minutes. This step crucial for beating texture later.
- In separate bowl, whisk flour with baking powder and salt. Measure precisely but flour here swapped to 2 cups cake flour plus 1/8 cup all-purpose for lighter crumb.
- Retrieve butter from bath, scrape remainder and solid bits in. Transfer butter to room temp bowl, beat 4 minutes till creamy pale color, lightens notably. This traps air, builds volume—don’t skip or rush.
- Add sugar plus vanilla. Beat medium-high until fluffy, about 3 minutes. Then beat in egg yolks one at a time, then whole eggs, mixing well after each. Should thicken smoothly, shiny texture.
- Alternate adding dry ingredients and milk in 3 additions starting and ending with dry. Stir gently with spatula after each addition, avoid overmixing but no streaks.
- Divide batter evenly into pans. Tap pans on counter to release any bubbles.
- Bake middle rack 38-43 minutes total. Rotate pans halfway, watch golden tops with slightly firm spring back. Toothpick test—pull it out clean or mostly clean. Cool cakes 18 minutes in pans. Invert onto racks, peel parchment after fully cool.
Dark Chocolate Mousse Filling
- Sprinkle gelatin over cold water. Let hydrate 6-8 minutes till softened.
- Whip cream until soft peaks form. Chill briefly until ready to fold in.
- Warm coffee liqueur about 40 seconds in microwave. Stir in gelatin until fully dissolved. Scrape bowl walls or gelatin lumps carefully.
- Beat egg yolks, sugar, salt on high until pale, thick, 4-5 minutes. Stream in coffee-gelatin liquid slowly while beating. Fold in melted chocolate, gently combine with rubber spatula.
- Fold whipped cream in two additions, light and deliberate to preserve airiness. Mousse should be thick, glossy, spreadable after chilling 30-45 minutes but can soften at room temp if too firm. No microwaving mousse to soften; patience matters.
Assembly
- Place one cake layer on platter. Spread mousse generously but evenly, no peaks needed. Dust mousse surface lightly with powdered sugar for texture and balancing bittersweet mousse.
- Top with second cake layer, press gently to secure but not squish mousse out.
- Frost cake all over with chocolate buttercream (control thickness for neater slices). Final dusting of powdered sugar adds visual contrast and slight sweetness.
- Rest cake chilled minimum 1 hour, flavors settle, mousse firms. Serve closer to room temp to let buttercream soften slightly.
Tips & Techniques
- Brown butter step—watch heat closely. Too hot burns; too cool no browning. Smell and color bigger markers than time. When browned bits clump and surface bubbles pop gently, done.
- Butter beating after chilling rounds out the texture. Butter straight from pan too liquid, ruins volume.
- Use bowl size wisely: eggs and sugar whipped in a room temp, dry ingredients sifted to avoid lumps.
- Mousse gelatin step ensures stable set; skip & mousse falls flat. Filter dissolved gelatin through fine mesh if needed to catch stray bits.
- Cake flour substituted gives a more delicate crumb than all-purpose.
- If no coffee liqueur, substitute cold brew concentrate or omit and add 1 tsp espresso powder dissolved in warm water.
- Rotating pans prevents uneven browning from oven hot spots. Better evenness in crumb.
- Cool cakes in pans first to prevent collapse but not so long they steam and sog.
- For frosting, temperature matters: too soft buttercream slides; too firm cracks. Beat to spreadable, not melting.
- Mousse can be made ahead up to 24 hours but must be tightly covered; bring to room temp before using.
- Use a sharp serrated knife to slice final cake for clean layers.
Cooking tips
Start with pan prep: shortening then parchment then flour for foolproof release. Brown butter slowly low heat—not too fast or solids burn. Those browned bits plus scent are your visual and aroma cues when done. Cooling in ice water bath solidifies butter enough for beating but keep timing flexible by watching edges firming up, not rigid. Whip butter after cooling to get volume, color shifts lighter means trapped air. Sugar and vanilla come in next, beat until fluff not grainy. Eggs must be added slowly, beating smooths lumps and incorporates air but avoid curdling—room temp eggs ideal. Flour beaten with baking powder and salt for leavening plus flavor. Mixing dry and milk alternately prevents batter collapse or overmixing. Pour batter evenly, tap pans to encourage bubble escape. Baking: watch for edges golden and springy rebound, toothpick need just short crumbs attached not raw batter. Allow cooling partially to firm crumb and easier handling, then flip out pans. Mousse gelatin blooms while cake bakes. Whip cream; do not skip chilling for better peaks and folding. Melt chocolate carefully—no scorching or you lose smooth gloss. Incorporate gelatin-liqueur liquid with egg yolks slowly to avoid scrambling eggs. Folding whipped cream must be gentle, preserve volume without lumps. Chill mousse to firm to spread but warm slightly before assembling if too stiff. Assembly: mousse to cake layer base; dust sugar to balance richness before stacking top layer. Frosting coats to seal layers and control moisture loss. Powdered sugar dust final touch, texture and sweetness contrast. Rest cake chilled to meld layers. Slice with serrated knife for clean cuts. Avoid microwave fixes for mousse softening; always use room temp waiting time.
Chef's notes
- 💡 Brown butter step requires patient low heat heating. Watch milk solids color and aroma for toasted nuts signals; chips clumping or bubbles popping means done. Not exact timing here—feel and smell more than watch clock.
- 💡 Flour swap done for crumb texture—mostly cake flour with a dash all-purpose prevents collapse; too much cake flour yields fragile crumb. Sift dry ingredients to avoid lumps and uneven leavening. Alternate dry and milk additions gently but thorough mixing.
- 💡 Gelatin must bloom completely in cold water; if lumps remain, strain through fine sieve to avoid gritty mousse. Coffee liqueur warms just enough to dissolve gelatin fully; skip microwave overshoot or mousse texture suffers. Folding whipped cream slow keeps lightness.
- 💡 Cake pans layered with shortening then parchment then flour—reduces stuck bits and ensures clean, even layers. Tap pans after filling to bust trapped air bubbles. Bake low and slow; rotating pans halfway prevents hot spots and uneven rise.
- 💡 Mousse gets firm in chill but can soften at room temp; avoid microwave fixes which ruin structure. Folding mousse uses two additions whipped cream—control volume with gentle, deliberate strokes. Frosting thickness affects slice clean cuts; aim steady spreadable consistency.
Common questions
How do I know when brown butter is done?
Watch milk solids color shifts from white to golden. Smell toasted nuts aroma. Bits clump up. Surface bubbles appear gently. Timing varies; rely on these sensory signals, not minutes alone.
What if I don't have coffee liqueur?
Substitute cold brew concentrate same amount or 1 teaspoon espresso powder dissolved warm water. Liquid helps gelatin dissolve better than dry alone. Can omit if needed but flavor changes less complex.
Why does mousse sometimes fall flat?
Usually gelatin not fully dissolved or whipped cream overmixed, deflating air. Use chilled cream, carefully fold; skip gelatine and mousse lacks stable set. Filter gelatin if lumps linger to keep mousse smooth.
How to store leftover cake?
Wrap tight in plastic wrap or store in airtight container. Refrigerate to keep mousse firm and prevent buttercream softening. Bring to room temp before serving for best texture. Freeze slices wrapped well; thaw slow.
