Chocolate Fudge Brownie Recipe

Preheat and prepare pan

Preheat the oven to 175°C (350°F). Line an 8x8 inch (20x20 cm) square baking pan with parchment paper, leaving an overhang on two opposite sides for easy removal. Lightly butter the parchment.

Measure and set ingredients

Measure out all ingredients. Chop the 170 g bittersweet chocolate into small pieces for melting and set aside the 150 g dark chocolate chunks. Roughly chop walnuts and reserve for topping.

Melt butter and chocolate

Place the 175 g butter and 170 g chopped bittersweet chocolate in a heatproof bowl set over a saucepan of simmering water (double boiler) with the bowl not touching the water. Stir occasionally until fully melted and smooth. Alternatively, microwave in 30-second bursts, stirring between, until melted. Remove from heat and let cool for 5 minutes.

Combine sugar and eggs

In a large bowl, whisk the 300 g granulated sugar and 3 large eggs together until well combined and slightly thickened (about 1 minute by hand or 30 seconds with a whisk/hand mixer). Stir in 1 tsp vanilla extract.

Incorporate chocolate mixture

Slowly pour the slightly cooled melted chocolate and butter into the egg-sugar mixture, whisking constantly to combine. Mixture will be glossy and thick.

Fold dry ingredients

Sift together 100 g all-purpose flour, 30 g unsweetened cocoa powder, and 1 tsp fine salt into the chocolate mixture. Gently fold with a rubber spatula until just combined and no streaks of flour remain. Do not overmix.

Add chunks

Fold in the 150 g dark chocolate chunks, reserving a small handful (about 2 tbsp) to sprinkle on top. This will ensure pockets of melted chocolate for a fudgey interior.

Transfer to pan

Scrape the batter into the prepared 8x8 inch pan and spread evenly with an offset spatula. Smooth the top but keep some texture.

Top with walnuts and chocolate

Scatter the roughly chopped 100 g walnuts evenly over the top, then sprinkle the reserved chocolate chunks. If using, dust 1 tbsp demerara sugar over the top for extra crunch and shine.

Bake

Bake in the preheated oven for 22–28 minutes. Check at 22 minutes: the edges should be set and slightly pulling away, and the center should still look moist with a few glossy cracks. A toothpick inserted into the center should come out with a few moist crumbs (not wet batter). Overbaking will reduce fudginess.

Cool

Remove from oven and immediately sprinkle with 1/4 tsp sea salt flakes if using. Let the brownies cool completely in the pan on a wire rack (about 1.5–2 hours) to set the fudgey interior. For cleaner slices, chill in the refrigerator for 30–60 minutes after cooling to room temperature.

Slice and serve

Use the parchment overhang to lift the cooled brownie slab from the pan. Place on a cutting board and cut into 9 or 12 squares using a sharp knife wiped clean between cuts for tidy edges. Serve at room temperature slightly warmed if desired.