Sheet Pan Vanilla Sheet Cake with Sprinkles

 

Cooking spray

3 cups all-purpose flour

1 3/4 cups granulated sugar

1 1/2 tsp. baking powder

3/4 tsp. salt

4 large eggs

3/4 cup canola oil, or melted and cooled unsalted butter

1 cup whole milk

1 T. vanilla extract

 

8 T. (1 stick) unsalted butter, at room temperature

3 cups powdered sugar

1 tsp. vanilla extract

1 T. whole milk

Disc sprinkles (optional)

 

Arrange a rack in the middle of the oven and heat to 350°F. Coat a 13×18-inch rimmed baking sheet (also known as a half sheet pan) with cooking spray; set aside. Whisk the flour, sugar, baking powder, and salt together in a large bowl. Add the eggs, oil or butter, milk, and vanilla and mix with an electric hand mixer on medium speed until smooth, about 3 minutes. Pour the batter into the baking sheet. Bake until the cake is lightly browned and springs back when gingerly pressed with a finger, 20 to 25 minutes. Cool the cake on a wire rack while preparing the frosting. Make the frosting: Beat the butter in a large bowl with an electric hand mixer on medium speed until smooth. Add the powdered sugar 1/2 cup at a time, beating well after each addition. Add the vanilla and milk and beat until smooth and fluffy. Spread the frosting right on top of the cake and use the tip end of a small spoon to work the frosting back and forth, creating a striped pattern. Decorate with sprinkles if using. NOTES: Storage: The cooled cake can be covered with plastic wrap and stored at room temperature for up to 2 days or refrigerated for up to 7 days.