Step 1: Preheat Oven u0026 Prepare Pan : Preheat oven to 350°F (175°C). Grease or line an 8x8-inch baking pan with parchment paper.
Step 2: Prepare Chocolate Brownie Batter : In a medium bowl, mix melted butter and sugar until smooth. Beat in eggs and vanilla extract. Sift cocoa powder, flour, salt, and baking powder, then fold into wet mixture until just combined.
Step 3: Prepare Pumpkin Swirl : In a small bowl, combine pumpkin puree, sugar, cinnamon, nutmeg, cloves, and vanilla extract until smooth.
Step 4: Assemble the Brownies : Pour brownie batter into prepared pan and smooth the top. Spoon pumpkin mixture in dollops over the chocolate batter. Using a knife or skewer, gently swirl the pumpkin through the chocolate to create a marbled effect.
Step 5: Bake : Bake for 30–35 minutes, or until the edges are set and a toothpick inserted in the center comes out with a few moist crumbs (do not overbake to keep fudgy texture). Cool in the pan on a wire rack for 15 minutes before slicing.
Step 6: Serve : Slice into 16 squares and serve at room temperature. Optionally, top with chocolate chips, nuts, or a dusting of powdered sugar. Perfect with coffee, milk, or a scoop of vanilla ice cream.