One-Bowl Brownie Bars with Espresso and Walnuts

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 developed and reviewed.

Dense, fudgy brownie bars enhanced with a hint of espresso and crunchy toasted walnuts, made in a single bowl for quick cleanup. This American-inspired recipe, ready in about 45 minutes, layers unsalted butter, granulated sugar, 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 230 calories and feeds 16, 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: 30 min Serves 16 American cuisine 230 cal/serving
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Ingredients

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Instructions

  1. Step 1: Preheat oven to 350°F. Lightly grease a 9x9-inch baking pan and line with parchment paper, leaving an overhang for easy removal.
  2. Step 2: In a large mixing bowl, whisk together 1 cup melted unsalted butter, 1 1/2 cups granulated sugar, 3/4 cup unsweetened cocoa powder, and 1 tbsp espresso powder until smooth and glossy.
  3. Step 3: Whisk in 1 tsp vanilla extract, then add 3 large eggs one at a time, beating well after each addition until the batter is thick and shiny.
  4. Step 4: Stir in 1 cup all-purpose flour and 1/2 tsp salt just until combined, then fold in 3/4 cup toasted chopped walnuts evenly.
  5. Step 5: Pour batter into prepared pan and spread evenly. Bake for 28-32 minutes, or until a toothpick inserted in the center comes out with moist crumbs.
  6. Step 6: Cool completely in the pan on a wire rack before lifting out using the parchment overhang. Cut into 16 bars and serve.

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