Optional toppings: Walnuts, sliced almonds, sprinkles or fresh berries
Instructions
White cake
Preheat the oven to 350°F. Butter a half sheet pan (13x18 inches) and set aside.
In a large bowl combine the flour, sugar, baking soda and salt. Set aside.
Heat the butter and water in a medium saucepan over medium heat. Bring to a light boil and then remove from heat and let sit 2 minutes (can use same pot for frosting). Then pour into the flour mixture. Stir until combined.
Stir in the sour cream, eggs and vanilla. Pour mixture into prepared pan.
Bake for 18-20 minutes, or until a toothpick comes clean.
Icing
Start making the icing as soon as the cake comes out. Melt the butter and milk in saucepan over medium heat. Once the mixture has melted and comes to a light simmer, remove from heat and whisk in vanilla and almond extract and a pinch of salt. Then slowly stir in powdered sugar. Beat with a handheld mixer to remove any lumps. It should be smooth and pourable.
Evenly pour the warm icing over the warm cake. Immediately spread out evenly with a rubber spatula. Add any toppings if desired (nuts and sprinkles need to be added right after frosting goes on).
Allow to cool and then cut into squares.
Notes
Make ahead: Make cake 24 hours ahead. Cover with foil and store at room temperature or in the fridge. Storage: Store leftovers in a covered container for up to 3 days. Freeze for up to 3 months. Nut lovers: Chop 1/2 cups walnuts or pecans and mix into the frosting. Recipe slightly adapted from my friend Kristyn's Lil Luna Cookbook in my Cookbook Fanatics Series