Martha Stewart Chocolate Sheet Cake

This martha stewart chocolate sheet cake is a rich and classic dessert, which is made with cocoa powder, semisweet chocolate, and sour cream. It’s a straightforward, crowd-pleasing recipe, perfect for parties and celebrations, ready in about 1 hour.

Martha Stewart Chocolate Sheet Cake Ingredients

• 1 1/2 sticks unsalted butter, room temperature, plus more for pan
• 1/2 cup boiling water
• 1/3 cup natural cocoa powder
• 3 oz semisweet chocolate, finely chopped
• 2 cups unbleached all-purpose flour
• 1 tsp baking powder
• 1/2 tsp baking soda
• 1 tsp kosher salt
• 1 1/2 cups granulated sugar
• 2 large eggs, room temperature
• 2 tsp pure vanilla extract
• 1 cup sour cream
• 1/2 recipe vanilla Swiss-meringue buttercream
• Chocolate curls, for serving (optional)

How To Make Martha Stewart Chocolate Sheet Cake

1. Prep oven and pan: Preheat oven to 350°F. Butter a 9×13-inch baking pan, line with parchment, butter parchment.
2. Bloom cocoa and chocolate: Stir boiling water with cocoa powder and chopped chocolate. Let cool 10 minutes.
3. Mix dry ingredients: Whisk flour, baking powder, baking soda, and salt in a bowl.
4. Cream butter and sugar: Beat butter and sugar on medium-high speed until fluffy, 2–3 minutes.
5. Add eggs and vanilla: Beat in eggs one at a time, then add vanilla.
6. Add chocolate mixture: Beat in cooled chocolate mixture until combined.
7. Alternate flour and sour cream: Reduce speed to low and beat in flour mixture in two batches, alternating with sour cream.
8. Bake cake: Spread batter evenly in prepared pan. Bake 35–40 minutes, until a tester shows a few moist crumbs.
9. Cool cake: Cool 10 minutes in pan, then invert onto a rack, remove parchment, and cool completely.
10. Frost and serve: Spread buttercream over top and sides. Garnish with chocolate curls if desired.

Recipe Tips

• Why use sour cream? It keeps the cake moist and tender.
• Top won’t spring back: This is normal for this cake style.
• Make-ahead tip: Cake can be baked 1 day ahead and wrapped at room temperature.
• Frosting substitute: Chocolate buttercream also works well.
• Best slicing tip: Use a long knife wiped clean between cuts.

What To Serve With Chocolate Sheet Cake

• Coffee or espresso
• Cold milk
• Vanilla ice cream
• Fresh berries

How To Store Chocolate Sheet Cake

Room Temperature: Wrap and store up to 1 day.

Refrigerate: Store wrapped up to 3 days; bring to room temperature before serving.

Chocolate Sheet Cake Nutrition Facts

• Calories: ~420
• Carbs: ~45g
• Protein: ~6g
• Fat: ~26g

Nutrition information is estimated and may vary.

FAQs

Can I make this cake ahead of time?
Yes, bake the cake a day ahead and frost before serving.

Can I use Dutch-process cocoa?
Natural cocoa is preferred for proper leavening.

Why is my cake very moist?
The cocoa bloom and sour cream create a soft crumb.

Can I skip the buttercream?
Yes, the cake is delicious plain or dusted with sugar.

Try More Recipes:

• Martha Stewart Chocolate Raspberry Cake
• Martha Stewart Chocolate Pudding Cake
• Martha Stewart Chocolate Pound Cake