1. Prep the Pans & Oven

Preheat the oven to 350°F (175°C).
Butter the bottoms of two 8-inch round cake pans, line with parchment paper, then butter and flour the lined pans.

2. Make the Cake Batter

In a stand mixer with the paddle attachment, cream the butter and sugar on high speed until light and fluffy (about 3 minutes).
Reduce speed to medium, then add the eggs one at a time, mixing well after each.
Beat in the sour cream, lemon zest, orange zest, and vanilla until fully combined.

In a separate bowl, sift together the flour, cornstarch, salt, and baking soda.
With the mixer on low, gradually add the dry ingredients to the wet, mixing until just smooth—don’t overmix.

3. Bake the Cakes

Divide the batter evenly between the two pans and smooth the tops.
Bake for 40–45 minutes, or until a toothpick inserted in the center comes out clean.

Let the cakes cool in the pans for 30 minutes, then turn out onto a wire rack and cool completely. (Wrap and freeze one layer if only making one cake.)

Assemble the Cake

Whip the heavy cream, sugar, and vanilla using the whisk attachment until stiff peaks form.

Using a serrated knife, slice one cake horizontally to create two layers.

Place the bottom layer on a serving platter. Spread with half the whipped cream and top with half the sliced strawberries.

Add the second layer, then finish with the remaining whipped cream and strawberries.