Tart Lemon Bars
By Emma
Certified Culinary Professional
•
Recipe tested & approved
Crisp buttery base with a tangy custard twist. Uses less sugar and a touch of cornstarch instead flour for the filling. Butter swapped for clarified butter in crust for better texture and shelf life. The lemon juice replaced partly by lime for a sharper punch. Cooling step extended to chill properly. Makes a 9x9 inch pan of zesty squares, perfect for portion control. Bakes in two stages for a firm crust and gently set filling. Visual cues over timers stressed. Powdered sugar finish masks slight cracks but adds sweetness balance. Great for those who want a tender yet sturdy lemon bar with a bit more zing and less cloying sweetness.
Prep:
25 min
Cook:
55 min
Total:
Servings:
36 squares
#French-inspired
#baking
#citrus desserts
#custard
#clarified butter
Crust crisp, firm. Filling tart but creamy, smooth but with body—lemon bars done right. Tried variations; flour filling gritty, lime juice too faint, butter soggy base. Learned to bake crust golden but not dark. Eyes on edges, not clock. Flick to tell if filling set—edges firm, center just shakes. Patience to chill bars is non-negotiable. Parchment overhang, my saving grace for neat squares. No nuts, less sugar, sharper citrus keeps bars lively yet balanced. Butter choice critical—clarified or melted, a game changer. Powdered sugar not just sweetness but covers cracks. Texture, taste, timing all must align. Small tweaks bring big payoff. These aren’t your average lemon bars. They bite with zest, hold with texture.
Ingredients
Crust
- 270 ml unbleached all-purpose flour (approx 1 1/8 cup)
- 50 ml powdered sugar (about 1/5 cup)
- 2.5 ml baking powder (1/2 tsp)
- 115 ml clarified butter or melted unsalted butter (1/2 cup)
Lemon Filling
- 200 ml granulated sugar (3/4 cup plus 1 tbsp)
- 20 ml cornstarch (about 4 tsp) instead of flour
- 100 ml fresh lemon juice (approx 1/3 cup)
- 60 ml fresh lime juice (about 2 tbsp)
- 2 eggs, room temp
- 60 ml heavy cream 35%
- Zest of 1 lemon
- Powdered sugar for dusting
About the ingredients
Flour slightly reduced to keep crust tender but stable. Powdered sugar replaces granulated for less gritty crust. Baking powder added for lightness, gluten network support. Butter choice matters—clarified butter keeps crust flaky longer, less moisture so less soggy base. Can swap clarified for unsalted melted butter if in a pinch, just expect slight softness. Cornstarch in filling makes custard thick without flour’s graininess. Tried tapioca flour once but texture was gummy. Citrus balance split between lemon and lime juice for brightness and layered aroma. Creme 35% keeps filling rich; don’t skip or risk runny custard. Zest adds punch; fresh mandatory. Powdered sugar dusting je ne regrette pas, hides cracks and adds some textural contrast. If allergy to dairy, coconut cream and vegan butter could work but adjust liquids. Keep eggs fresh for best emulsification. Chill is non-negotiable for clean cuts.
Method
Crust
- Set oven rack to middle. Preheat to 175 C (350 F). Line a 23 cm (9 inch) square pan with parchment leaving overhang for easy removal. No greasing; the paper does the job.
- Mix flour, powdered sugar, and baking powder in a bowl. Add clarified butter with fingertips. Use a light touch to work in butter until dough just holds together without being greasy or crumbly. No need to overhandle or it turns tough.
- Press dough evenly into pan base. You want a firm, level layer. If dough resists, chill 5 minutes before pressing again.
- Bake approx 28 minutes until the edges start turning golden but center still pale. Shouldn't brown too much or crust gets dry and crumbly later.
Filling
- While crust bakes, whisk sugar with cornstarch until blended. The starch is key here—stiffer than plain flour, helps custard thicken without turning gritty.
- Add lemon and lime juice, eggs, cream, and lemon zest. Beat until fully homogenous. Watch to not mix in too much air—custard works best slightly dense.
- Once crust comes out, immediately pour filling over hot base. If crust cools, filling won't bind properly.
- Drop oven temp to 160 C (320 F). Bake 22 to 27 minutes. Edges set and barely jiggle center. You'll know by gentle shake.
- Remove from oven. Let cool at room temp for an hour or so—don't rush or filling splits.
- Chill min 4 hours or overnight. Longer chill firms bars for clean slicing.
- Use parchment overhang to lift block from pan. Cut into 36 even squares. Dust with powdered sugar just before serving. The sugar hides tiny cracks and adds hint of sweetness.
Tips & Tricks
- Clarified butter stops soggy crust, lasts longer. No nuts here—easy swap to almond flour in crust if desired.
- Lime juice adds zesty sharpness; try grapefruit or orange zest for citrus twist. Cornstarch avoids graininess common with plain flour in custards.
- Don’t overbake or filling gets rubbery. Look for that light jiggle at center—like panna cotta set but still wobbly.
- If crust browns too fast in your oven, tent with foil halfway through first bake.
- Parchment overhang is a life saver for neat removal. Chill bars thoroughly; warm bars crumble when cut.
- Powder sugar can be swapped for finely grated white chocolate or coconut flakes to vary finish.
- Cold eggs separate easier and better emulsify in filling. If too warm, curdling risk increases. Always strain filling if you want ultra-smooth texture but I like the bits of zest keeping bite.
Cooking tips
Start by prepping oven and paper lined pan carefully; parchment overhang saves scraping disasters. Mix dry crust ingredients well before adding butter—no lumps. Butter in with fingers until dough forms like sandcastles—hold shape but still soft. Press evenly, chill if sticky or too soft. Bake crust till edges hint gold, center slightly pale. Not too brown or crust ruins final mouthfeel. Prepare filling while crust bakes, whisk to emulsify sugar and starch. Add citrus and eggs carefully; room temp eggs integrate best, less curdling risk. Pour on warm crust immediately to help filling set evenly. Lower oven temp so filling cooks gently—120 degrees (320 F) ideal to avoid over-firm edges and cracked top. Watch edges firm before jiggle center; overbaking makes rubbery custard. Cool fully, then chill minimum 4 hours. Long chilling prevents crumble when slicing. Use parchment lifts, sharp knife for best cuts. Dust with powdered sugar just before serving. Practice sensing doneness by wobble, color, and edge firmness—not only timers. Tent crust if browning too fast with foil. These few steps define success or failure.
Chef's notes
- 💡 Clarity on clarified butter is key. Stops soggy bottom, makes crust flaky longer. Melted unsalted butter works but expect slight softness. Don't skip chilling dough if sticky. Press evenly. Crust edges should turn pale gold, center stay light. No browning; dry crumbly later. When parchment overhang is there, use it for lifting bars out clean—skip scraping pan nightmare.
- 💡 Filling needs whisking sugar with cornstarch before adding citrus and eggs. Cornstarch makes custard thick but not gritty, unlike flour. Zest adds punch; no dry peels. Beat just enough to combine, avoid air bubbles. Eggs room temp only; cold eggs break emulsions, hot eggs curdle. Pour warm crust immediately after bake or filling won't set well. Timing matters in pouring stage.
- 💡 Watch baking by sensory cues not clock. Crust bake first stage 28 minutes approx. Filling second bake lower temp 160 C (320 F). Edges firm, center Jiggle but not liquid. Jiggle like panna cotta set but wobbly. Overbake and custard turns rubbery, cracks more. When crust browns unevenly, tent foil halfway. Keeps crust golden and moist. Chill bars min 4 hours; slicing clean depends on cold firm filling.
- 💡 Powdered sugar on top hides tiny cracks that form from chilling and baking stresses. White chocolate or coconut flakes can swap for powdered sugar if variation wanted. Parchment lift essential; no greasing pan traps moisture to soften crust. Use a sharp knife—clean slices start with chilled bars then clean blade wipe between cuts. No rushed cooling, or bars crumble. Patience wins here.
- 💡 If you want citrus twist beyond lemon-lime, add grapefruit or orange zest separately. Careful with zest quantity; too much bitter or overly fragrant. Cornstarch over flour in filling avoids grainy custard texture. Tried tapioca flour once, gummy. Heavy cream 35% keeps richness; leave out and custard runs thin. Clarified butter makes a big texture difference; swap only when desperate. Room temp eggs help emulsify filling nicely.
Common questions
Why use clarified butter?
Stops soggy crust, holds flaky texture longer. Melted unsalted butter okay but softer results. Clarified has less moisture and milk solids removed. Crust last better. I noticed immediate crisp edges are sharper with it.
Cornstarch instead of flour why?
Cornstarch thickens without graininess. Flour gives slight grit if overmixed. Cornstarch makes custard silkier but firm. Tried tapioca but texture weird, gummy. Cornstarch also more stable under heat for longer bake times here.
Filling cracks on top?
Usually from cooling too fast or overbake. Edges firm and center wobbly when done. Crack forms when custard shrinks or dries. Chill gently and fully. Cover pan to keep humidity. Stop bakes right with jiggle left. Avoid air bubbles mixing in filling; strain if needed.
How store bars?
Keep chilled wrapped tight. Fridge up to 3 days no problem. Freeze individually wrapped or whole block wrapped airtight. Thaw in fridge overnight. Powder sugar topping best added after thawing. Can store pan covered at room temp max 12 hours but bars soften fast.
