Tangy Lemon Sheet Cake (Print Version)
# Ingredients:
→ Shortbread Base
01 -
3 cups crushed shortbread cookies (about 11-15oz blended into fine crumbs)
02 -
5 tablespoons melted unsalted butter
03 -
1 tiny dash salt
→ Lemon Cake Layer
04 -
1 tablespoon grated lemon peel (roughly 1 lemon)
05 -
3/4 cup room temp buttermilk
06 -
2/3 cup room temp sour cream
07 -
3 whole eggs at room temp
08 -
1 egg white at room temp
09 -
1 tablespoon pure vanilla extract
10 -
1 teaspoon lemon extract (if you want)
11 -
1/3 cup veggie oil
12 -
1/4 cup plain flour
13 -
1 box (15.25oz) lemon cake mix (try Duncan Hines)
→ Lemon Filling
14 -
3 egg yolks
15 -
1 whole egg
16 -
3/4 cup white sugar
17 -
1/2 cup fresh lemon juice
18 -
2 tablespoons grated lemon rind (roughly 2 lemons)
19 -
4 tablespoons unsalted butter
→ Lemon Frosting
20 -
1 1/2 cups barely softened unsalted butter
21 -
1 teaspoon lemon extract
22 -
1 tablespoon vanilla extract
23 -
1 tiny dash salt
24 -
1/4 cup heavy cream
25 -
6-7 cups confectioners sugar
26 -
1 drop yellow food gel coloring
→ Garnish
27 -
1 cup crumbled shortbread cookies
# Instructions:
01 -
Lightly coat a 9x13 baking dish with shortening then dust with flour to stop sticking. Warm your oven to 325°F (165°C).
02 -
Grind shortbread cookies until they're super fine, then scoop 3 cups into a bowl. Mix in the melted butter and salt, making sure all crumbs get coated. Push mixture firmly into your pan, using a glass bottom to flatten it evenly.
03 -
Grab a big bowl and whisk together the lemon zest, buttermilk, sour cream, eggs, egg white, vanilla, lemon extract (if you're using it), oil, and flour. Sift the cake mix on top and stir gently until just mixed.
04 -
Pour your batter right on top of the unbaked cookie base. Stick it in the oven for 28-30 minutes or until you can poke it with a toothpick and it comes out clean. Let it cool completely in the pan before you start decorating.
05 -
While your cake's baking, put egg yolks, whole egg, sugar, lemon juice, and zest in a pot over medium heat. Keep whisking for about 6 minutes until it gets thick enough to coat a spoon. Take it off the heat and stir in butter until melted. Strain out the zest bits. Cover the surface directly with plastic wrap and chill until cold.
06 -
Using a stand mixer with the paddle, beat butter for about a minute until fluffy. Toss in salt, both extracts, and heavy cream, mixing until blended. Add powdered sugar bit by bit, around 1/2 cup at a time. Add the yellow coloring. Beat on high for a minute to fluff it up, then slow for 30 seconds to knock out bubbles.
07 -
Spread most of your frosting evenly over the cooled cake. Save about 1 1/2 cups in a piping bag with a 1M tip. Make pretty lines of frosting shells in rows. Fill the gaps between your piped frosting with the chilled lemon filling.
08 -
Scatter crumbled shortbread cookie pieces across the top for some crunch and extra shortbread flavor.
# Notes:
01 -
This treat brings together sweet-tart lemon bar flavors in a soft sheet cake format
02 -
You can keep it covered in your fridge for up to 3 days
03 -
The flavors really pop when you let it sit out before eating