Jump to recipeDessert · Cake

Yellow Sheet Cake with Chocolate Frosting

A soft, buttery yellow cake and thick chocolate buttercream make a dependable pan dessert for potlucks, birthdays, and easy sharing.

Golden yellow sheet cake in a pan with thick chocolate frosting spread in soft swirls.

This familiar sheet cake keeps the method straightforward: cream butter and sugar, build a smooth batter with eggs and milk, then bake it in one pan. A cocoa buttercream goes on after the cake cools, so each slice has a tender crumb under a generous chocolate layer.

Start with room-temperature ingredients

Softened butter can trap air as it beats with the sugar, while room-temperature eggs and milk blend into that base more evenly. The resulting batter should look creamy and cohesive before the dry mixture goes in.

Cream until the mixture looks lighter

The butter and sugar need a few minutes together to become pale and fluffy. Scraping the bowl helps avoid pockets of dense butter, which can leave the finished cake uneven.

Smooth yellow cake batter is spread into the corners of a greased rectangular pan. — The smooth yellow batter is spread level in the prepared pan before baking.

Alternate the flour and milk gently

Adding the dry mixture and milk in turns helps them incorporate without overworking the batter. Begin and end with flour, and stop mixing as soon as the last dry streak disappears for a tender crumb.

Let the cake cool before frosting

A full cool gives the cake time to set and keeps the buttercream from melting into the surface. Make the frosting while the pan cools, then spread it over the cake once the center and edges feel completely cool.

A close slice reveals tender yellow cake under a thick layer of chocolate buttercream. — A close view shows the fine yellow crumb beneath a thick, softly swirled chocolate frosting.

Serve and keep the slices tender

The frosting and crumb are softest at room temperature, making the cake easy to cut and serve from its pan. Cover leftovers tightly and keep them at room temperature for up to three days.

Yellow Sheet Cake with Chocolate Frosting

16 slices

135 minutes total

Ingredients

• 2 1/2 cups all-purpose flour
• 2 1/2 tsp baking powder
• 1 tsp fine salt
• 1 cup unsalted butter, softened, including 1 tbsp for the pan
• 1 3/4 cups granulated sugar
• 4 large eggs, at room temperature
• 2 tsp vanilla extract for the cake
• 1 cup whole milk, at room temperature
• 1/2 cup unsalted butter, softened for the frosting
• 2/3 cup unsweetened cocoa powder
• 3 cups confectioners' sugar
• 1/3 cup whole milk for the frosting
• 1 tsp vanilla extract for the frosting
• 1/4 tsp fine salt for the frosting

Method

Heat the oven and prepare the pan
Set a rack in the center and heat the oven to 350 F. Grease a 9-by-13-inch pan with 1 tbsp from the measured cake butter, keeping the rest for the batter.
Look for: The oven is fully preheated and the pan has a thin, even butter coating.
Whisk the dry ingredients
Whisk the all-purpose flour, baking powder, and fine salt together in a medium bowl until the leavening is evenly dispersed.
Look for: No visible baking powder clumps remain in the flour.
Cream butter and sugar
Beat the remaining softened cake butter with the granulated sugar on medium speed until pale and fluffy, scraping the bowl once so no dense butter remains at the bottom.
Look for: The mixture looks lighter in color and holds soft ridges from the beaters.
Add eggs and vanilla
Beat in the room-temperature eggs one at a time, letting each disappear before adding the next, then mix in the cake vanilla extract until smooth.
Look for: The batter is cohesive and creamy rather than curdled or streaky.
Finish the batter
On low speed, add the flour mixture in three additions, alternating with the room-temperature whole milk in two additions; begin and end with flour, and stop as soon as the last dry streak disappears.
Look for: The batter is thick, smooth, and free of dry flour without looking elastic.
Bake the cake
Scrape the batter into the prepared pan and spread it evenly into the corners. Bake at 350 F for 32 to 36 minutes, until the center springs back lightly and a tester comes out without wet batter.
Look for: The top is evenly golden, the center springs back, and a tester shows a few moist crumbs rather than wet batter.
Cool the cake
Let the cake cool in its pan for 15 minutes, then loosen the edges and set the pan on a rack until the cake is completely at room temperature, about 45 minutes more.
Look for: The pan no longer feels warm and the cake surface is cool before frosting.
Make the chocolate frosting
While the cake cools, beat the frosting butter until smooth. Sift in the cocoa powder and confectioners' sugar, then beat in the frosting milk, frosting vanilla, and frosting salt until the buttercream is smooth and spreadable.
Look for: The cocoa is fully blended and the frosting spreads without running.
Frost the cake
Spread the chocolate buttercream in a generous, even layer over the completely cooled cake, reaching the corners without pressing hard enough to tear the crumb.
Look for: The frosting covers the cake edge to edge with soft swirls across the top.
Serve and store
Cut the cake into 16 portions and serve at room temperature for the softest crumb. Cover the pan tightly and keep it at room temperature for up to 3 days; bring any chilled portion back to room temperature before serving.
Look for: The cake slices cleanly and the buttercream is soft enough to yield to a fork.