Fudgy Chocolate Brownie Tray Bake

Prep the tin & oven

1. Preheat the oven to 180°C / fan 160°C / gas 4. Line a 23×33cm tray bake tin with parchment, leaving overhang on the long sides — this becomes a handle to lift the brownie out cleanly later.
2. Weigh out everything before you start. Brownies don't wait.

Make the batter

1. Melt the butter and chocolate together in a heatproof bowl over a pan of barely simmering water. Don't let the bowl touch the water. Stir until smooth, then take it off the heat and let it cool for 5 minutes.
2. Whisk the eggs, both sugars, and vanilla together for a full 4-5 minutes — you want the mix pale, thick, and doubled in volume. This is what gives you the glossy, crackly top. Don't skip the full timer.
3. Pour the cooled chocolate-butter mix into the eggs and fold gently until you have a uniform colour. Work slowly — you don't want to knock the air out.
4. Sift the flour, cocoa, and salt directly into the bowl and fold until just combined. Stop as soon as you can't see any streaks of flour. Fold in the chocolate chunks if using.

Bake

1. Pour the batter into your lined tin and smooth the top with a spatula. Give the tin a gentle tap on the counter to settle it.
2. Bake for 26-30 minutes. The brownie is ready when the top is set and shiny with a gentle wobble in the middle and a skewer comes out with moist crumbs (not wet batter, not clean).
3. Cool completely in the tin on a rack — at least 2 hours, ideally longer. Cutting warm brownies is how you get ragged squares.

Cut & store

1. Lift the slab out of the tin using the parchment handles. Trim any dry edges.
2. For clean commercial-grade squares, warm a long knife under hot water and dry it between each cut. A 4×6 grid gives you 24 squares; 5×6 gives 30 smaller ones for boxes.
3. Store in an airtight container at room temperature for 3 days. Freeze, tightly wrapped, for up to 2 months.