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Snack

Chocolate Sheet Cake with Fudge Frosting

A thin, fudgy chocolate cake in a half-sheet pan, with a glossy cocoa frosting poured over while it’s warm. Feeds a crowd, ready in about an hour.

⏱ 1 hr 30 min (20 min prep, 25 min cooking, 45 min waiting) 🍽 Serves 24 · 1 square, frosted kid friendlymake aheadfreezer friendly vegetarian

In our collection Birthday parties: menu and shopping list β†’

πŸ“… Add to my plan

ContainsMilk, Eggs, Wheat. Check the labels on what you buy; brands differ.

Ingredients

Make 24 servings

  • Cake

  • 2 cup All-purpose flour
  • 2 cup Granulated sugar
  • 1 tsp Baking soda
  • Β½ tsp Table salt
  • 1 cup Butter, unsalted, 2 sticks
  • β…“ cup Unsweetened cocoa powder
  • 1 cup Water
  • Β½ cup Buttermilk
  • 2 Eggs, large
  • 1 tsp Vanilla extract

  • Frosting

  • Β½ cup Butter, unsalted, 1 stick
  • β…“ cup Unsweetened cocoa powder
  • β…“ cup Whole milk
  • 3Β½ cup Powdered sugar
  • 1 tsp Vanilla extract

Make it yourself

Make the butter yourself β†’ Out of buttermilk? Make it β†’ Out of powdered sugar? Make it β†’

In the planner, Make it on the shopping list swaps the store item for these ingredients and puts the work on your prep day.

Nutrition

Nutrition coming: the USDA numbers for these ingredients are being added.

Steps

You’ll need: half-sheet pan (13 by 18 inches), two saucepans, large mixing bowl, whisk, spatula.

  1. Heat the oven to 350Β°F and grease the half-sheet pan.
  2. Whisk the flour, sugar, baking soda and salt in a large bowl.
  3. In a saucepan, bring the butter, cocoa and water to a boil, stirring. Pour it over the flour mixture and whisk until smooth.
  4. Whisk in the buttermilk, eggs and vanilla. Don’t eat or taste the raw batter, and don’t let kids lick the spoon: raw flour and raw eggs can carry germs (FDA). Bake it first.
  5. Pour into the pan and spread it to the corners. Bake 18 to 22 minutes, until a toothpick in the center comes out clean.
  6. About 5 minutes before the cake is done, make the frosting: melt the butter with the cocoa and milk in a saucepan, bring just to a simmer, take it off the heat and whisk in the powdered sugar and vanilla until smooth.
  7. Pour the warm frosting over the hot cake and spread it quickly; it sets as it cools. Cool at least 30 minutes before cutting into 24 squares.
Make aheadBake the day before; keep it covered at room temperature.
❄️ FreezerFreeze squares between layers of parchment up to 2 months.
β†Ί LeftoversKeep covered at room temperature up to 3 days.
πŸ§’ With kidsKids can whisk the dry ingredients and help pour the cooler parts. A grown-up handles the boiling butter and the hot frosting.
Buttermilk swapUse Β½ cup milk with 1Β½ teaspoons vinegar stirred in.
Nuts swapMany families scatter chopped pecans over the frosting; leave them off for a nut-free party.

Goes well with

πŸ‹ Fresh-Squeezed Party Lemonade

Good to know

All-purpose vs. bread flour (and friends) Baking soda vs. baking powder Table salt vs. kosher salt vs. sea salt Cooking Fats Compared Salted vs. unsalted butter

An original Teddy Rook Book recipe, written for our Birthday parties collection; safety steps follow USDA. Nutrition is estimated from USDA FoodData Central and changes with brands and portions.