Introduction

This Lemon Custard Cake is a delicate dessert with a light, custardy center and a bright citrus flavor. It’s wonderfully simple to make and perfect for those who love a tart yet sweet treat. The unique texture comes from the soft egg white lumps baked into the top layer, giving it a charming homemade appeal.

A close-up of a square piece of lemon cake resting on a white plate, showing three visible layers: a pale yellow dense and moist bottom layer, a light and fluffy middle layer of lemon cake, and a thin top layer dusted with powdered sugar giving a soft white texture. The cake surface has a slight crumbly look and there are small lemon peel bits around the plate. Other pieces of the same cake are blurred in the background on the white marbled texture. photo taken with an iphone --ar 4:5 --v 7

Ingredients

4 eggs (room temperature) – separated
¾ cup sugar
½ cup unsalted butter – melted and slightly cooled
1 teaspoon vanilla extract
¾ cup all-purpose flour
¼ cup freshly squeezed lemon juice
Grated zest from 2 large lemons
1 ¾ cups milk – lukewarm
Powdered sugar for dusting

Instructions

Step 1: Preheat the oven to 325°F. Line an 8×8-inch baking dish with parchment paper, leaving an overhang on the sides. Lightly grease the parchment with cooking spray, then set aside.
Step 2: Whip the egg whites until stiff peaks form, then set aside.
Step 3: In a separate bowl, beat the egg yolks and sugar together until the mixture is pale yellow.
Step 4: Add the melted butter and vanilla extract to the egg yolk mixture and mix until well combined.
Step 5: Gradually mix in the flour until fully incorporated.
Step 6: Stir in the lemon juice and grated lemon zest until evenly mixed.
Step 7: Slowly beat in the lukewarm milk until the batter is smooth and well combined.
Step 8: Add the whipped egg whites and whisk by hand. Do not fold completely; leave small lumps of egg whites. These will float on the batter’s surface during baking and create the top layer.
Step 9: Pour the thin batter into the prepared pan and bake for 40 to 60 minutes. Check after 35 minutes; the cake should be barely jiggly in the center but have a firm top. If the top browns too quickly, cover it loosely with aluminum foil.
Step 10: Allow the cake to cool completely before dusting with powdered sugar and serving.

Tips & Variations

For a stronger lemon flavor, add extra lemon zest or a teaspoon of lemon extract.
If you prefer a smoother top, gently fold the egg whites completely before baking, but the traditional lumps add a unique texture.
Use fresh lemon juice rather than bottled for the best bright, natural flavor.
Make sure not to overbake to keep the custard center soft and creamy.

Storage

Store any leftover cake covered in the refrigerator for up to 3 days. When ready to serve again, allow it to come to room temperature or warm slightly in the microwave for a few seconds to restore its custardy texture.

How to Serve

The image shows a thick, square lemon bar with two visible layers: a dense, smooth, pale yellow bottom layer and a fluffy, lighter yellow top layer with a slightly browned crust. The top is covered with a dusting of white powdered sugar, giving it a soft, snowy texture. The lemon bar sits on a white marbled surface, with small crumbs and bits of lemon zest scattered around. In the background, there are several more lemon bars, slightly out of focus, displaying the same layers and texture. Photo taken with an iphone --ar 4:5 --v 7

Serve this delicious recipe with your favorite sides.

FAQs

Can I use a different pan size?

An 8×8-inch pan is recommended for the right thickness, but you can use a similar-sized pan. Adjust the baking time accordingly and start checking for doneness earlier or later depending on the pan’s depth and material.

Why is the batter so thin?

The batter’s thinness comes from the combination of milk and beaten egg whites. This creates a light custard texture but can seem unusual compared to typical cake batters. The thin batter ensures a soft, delicate result.