One-Bowl Chocolate Peanut Butter Sheet Cake

By AislePrompt Editorial · ·

How this recipe was made — this recipe was drafted by AislePrompt's AI-assisted pipeline from technique templates and USDA-sourced nutrition data, and published by AislePrompt Editorial — see how AislePrompt recipes are drafted and published.

A moist chocolate sheet cake swirled with peanut butter, baked in one bowl for easy preparation and indulgent flavor. This American-inspired recipe, ready in about 55 minutes, layers all-purpose flour, granulated sugar, unsweetened cocoa powder into a dessert worth slowing down for — great for weekend baking, holiday tables, or any time you want a sweet payoff at the end of a meal. Each serving lands at about 320 calories and feeds 12, so it slots into a weekend bake or a special-occasion dessert tray. Tap "Plan a meal with the AI" below to drop this recipe into your week and send the ingredients straight to Instacart. Nutrition values are approximate, calculated from USDA FoodData Central (fdc.nal.usda.gov) — verify against ingredient labels for any health-driven dietary plan.

Prep: 15 min Cook: 40 min Serves 12 American cuisine 320 cal/serving
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Ingredients

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Instructions

  1. Step 1: Preheat the oven to 350°F. Grease and flour a 9x13-inch baking pan.
  2. Step 2: In a large mixing bowl, whisk together 1 3/4 cups all-purpose flour, 2 cups granulated sugar, 3/4 cup unsweetened cocoa powder, 1 1/2 teaspoons baking soda, and 1 teaspoon salt until well combined.
  3. Step 3: Add 1 cup buttermilk, 1/2 cup vegetable oil, 2 large eggs, and 2 teaspoons vanilla extract to the dry ingredients. Beat with an electric mixer on medium speed for 2 minutes until smooth.
  4. Step 4: Gradually stir in 1 cup hot water (batter will be thin) until fully incorporated.
  5. Step 5: Pour the batter evenly into the prepared pan.
  6. Step 6: Drop spoonfuls of 1/2 cup creamy peanut butter over the top of the batter. Use a knife or skewer to swirl the peanut butter gently through the batter to create a marbled effect.
  7. Step 7: Bake for 35-40 minutes, or until a toothpick inserted into the center comes out with a few moist crumbs.
  8. Step 8: Let the cake cool completely in the pan before slicing and serving.

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