Lemon Layer Cake

This is a lemon cake times three. Not only does it boast a superior lemon-flavored cake, but it’s filled with Meyer lemon–laced curd, then finished with a creamy lemon frosting. But it is not only for those obsessed with lemon flavor: Our kids adore it. And, by the way, it’s gluten-free. In fact, it’s been requested so regularly that we figured out other ways to enjoy it (see the variations on here).

By the way, don’t be thrown by the use of xanthan gum, which is available in many supermarkets and baking-goods stores. It’s a natural emulsifier that ensures volume in this gluten-free cake. Can’t get Meyer lemons? The regular kind also work beautifully. But buy organic lemons, if available, as this recipe uses a lot of zest. You will need to zest and squeeze three or four lemons—remember to zest them before juicing.

The layers can be made (but not halved) a day ahead. Cool them completely, wrap with plastic wrap, and keep at room temperature. The curd can be prepared and chilled up to 3 days in advance. The frosting can also be made a day ahead and refrigerated. (Remember to bring it to room temperature before spreading.)

MAKES 8 TO 10 SERVINGS

Cake

2 cups brown rice flour

⅔ cup potato starch

⅓ cup tapioca flour

1 tablespoon baking powder

1 teaspoon xanthan gum

½ teaspoon kosher salt

1 cup low-fat milk

1 cup grapeseed oil

1 teaspoon pure vanilla extract

1 tablespoon finely grated lemon zest

2 cups sugar

4 extra-large eggs

Lemon Curd

6 extra-large egg yolks

1 extra-large egg

½ cup plus 4 tablespoons sugar

Finely grated zest of 1 lemon

½ cup Meyer or regular lemon juice (from 3 to 4 lemons)

Pinch of kosher salt

8 tablespoons (1 stick) unsalted butter, at room temperature, cut into 16 pieces

Frosting

1 cup (2 sticks) unsalted butter, softened

3½ cups confectioners’ sugar

2 teaspoons finely grated lemon zest (from 1 to 2 lemons)

¼ cup Meyer or regular lemon juice

To make the cake layers, position a rack in the middle of the oven and preheat the oven to 350°F. Brush two 9-inch round cake pans with oil. Line the bottom of each pan with a round of parchment paper, then oil the paper.

In a medium bowl, whisk together the brown rice flour, potato starch, and tapioca flour. Measure 2½ cups of this mixture into a second medium bowl. (Save or discard the remaining mixture.) Add the baking powder, xanthan gum, and salt and mix well.

In another medium bowl, mix together the milk, oil, vanilla, and lemon zest.

In the bowl of an electric mixer, combine the sugar and eggs and beat at medium speed until just combined, about 1 minute. Reduce the speed to low and add the flour and milk mixtures alternately in 3 batches, beginning and ending with the flour mixture. Mix until just combined.

Divide the batter evenly between the pans and smooth the tops with a spatula. Bake until a wooden pick or skewer inserted in the center of each layer comes out clean, 35 to 40 minutes. Cool the layers in their pans on racks for at least 10 minutes. Run a thin knife around the edge of one cake layer, place a rack over the pan, and invert the cake onto the rack. Repeat with the second layer and second rack. Peel off the paper and cool the layers completely. Re-invert so the layers are right side up.

Meanwhile, make the lemon curd. In a medium bowl, whisk together the egg yolks, whole egg, and sugar. Add the lemon zest, lemon juice, and salt. Fill a medium saucepan with 2 inches of water and bring to a simmer over medium heat. Place the bowl over the saucepan and whisk briskly until the mixture has doubled in volume and holds the lines made by the whisk, 7 to 10 minutes.

Fill a large bowl with ice and add enough water to make an ice bath. Place the bowl with the curd mixture in the ice bath and let cool, stirring occasionally, until the mixture is just warm to the touch. Be careful not to get any water in the curd. Add the butter gradually, mixing until it’s completely combined. Chill the curd until ready to use.

To make the frosting, beat the butter with an electric mixer at high speed until light and fluffy, about 2 minutes. Reduce the speed to low and add the confectioners’ sugar, lemon zest, and lemon juice. Mix until creamy and smooth, 3 to 5 minutes.

To assemble the cake, using a long serrated knife, halve each of the cooled cake layers horizontally. Divide the curd into thirds. Place the first cake layer on a cake plate, cut side down, and spread with a portion of curd. Repeat with the other 2 layers. The last layer will get the lemon frosting. Frost the top and sides or just the top of the cake.

CUPCAKE VARIATIONS

The cake components are very versatile. The cake batter can be used to make 12 large or 18 regular-size cupcakes. Bake them at 350°F for 25 to 30 minutes. Scoop out their centers with a spoon, fill them with the curd, and frost. Or frost the cupcakes with a thin layer of raspberry jam. Or top with a layer of curd or frosting and add a fresh raspberry to each cupcake.

TART AND TRIFLE VARIATIONS

The curd also makes a great tart filling. Just pour it into a partially baked sweet pastry shell or Our Pie Crust (here). Bake at 350ºF until the curd is firm and the crust is golden brown, 10 to 15 minutes. Or layer the curd with pound cake, berries, and whipped cream to make a delicious trifle.