1. Prepare for Baking: Setting the Stage for Success

1. Preheat Oven: Preheat your oven to 325°F (160°C) with a fan, or 338°F (170°C) for conventional heating.
2. Line Baking Tray: Line a large baking tray with parchment paper. This will prevent the brookies from sticking and make cleanup a breeze.

2. Melt Chocolate and Butter: Creating a Rich Chocolate Base

1. Combine Chocolate and Butter: In a heatproof bowl, combine the chopped dark chocolate (225g) and butter (56g).
2. Melt Using a Double Boiler: Place the bowl over a pan of simmering water, making sure the bottom of the bowl does not touch the water. This gentle heat will melt the chocolate and butter without scorching them.
3. Stir Occasionally: Stir the chocolate and butter mixture occasionally until it’s fully melted and smooth.
4. Add Vanilla: Remove from heat and stir in vanilla extract.
5. Set Aside: Set the melted chocolate mixture aside to cool slightly.

3. Whip Eggs and Sugars: Achieving a Light and Airy Texture

1. Combine Eggs and Sugars: In a separate medium bowl, combine the caster sugar (100g), demerara sugar (90g), and eggs (2).
   • Note: The recipe calls for caster sugar, which is finer than granulated sugar. If you don’t have caster sugar, you can use granulated sugar, but the texture of the brookies may be slightly different.
2. Whisk Vigorously: Using an electric hand whisk on high speed, beat the mixture until it becomes very light, thick, and fluffy. This should take several minutes. The mixture will increase in volume and lighten in color.

4. Combine Dry Ingredients: Ensuring Even Distribution

1. Sift Together: In another bowl, sift together the all-purpose flour (95g), cocoa powder (2 tablespoons), baking powder (1 teaspoon), and salt (¼ teaspoon). Sifting helps to remove any lumps and ensures the dry ingredients are evenly mixed.
2. Add Chocolate Chips: Add the chocolate chips (85g) to the dry ingredients and stir to combine.

5. Integrate Chocolate Mixture: Bringing the Flavors Together

1. Gradually Fold: Gradually fold the melted and slightly cooled chocolate and butter mixture into the whipped eggs and sugars.
   • Tip: Use a large rubber spatula and a gentle folding motion to avoid deflating the whipped eggs.
2. Stir Gently: Stir until the chocolate mixture is just incorporated into the egg mixture.

6. Fold in Dry Ingredients: Completing the Batter

1. Add Dry Ingredients: Carefully fold the dry ingredients (flour mixture with chocolate chips) into the wet mixture using a spatula.
2. Mix Until Just Combined: Mix only until just combined. Do not overmix. The batter should be thick and fudgy.

7. Bake the Brookies: Achieving the Perfect Texture

1. Scoop Batter: Scoop out tablespoons of the batter onto the prepared baking tray.
   • Tip: A cookie scoop can help ensure even portions.
2. Space Apart: Leave ample space (about 2 inches) between each brookie, as they will spread during baking.
3. Bake: Bake in the preheated oven for 12-14 minutes.
   • Check for Doneness: The brookies are done when they are set around the edges and have a slightly crackly top. The centers should still be a bit soft and fudgy.
   • Tip: Do not overbake, or the brookies will be dry.

8. Cool and Finish: The Final Touches

1. Sprinkle with Sea Salt (Optional): If desired, immediately sprinkle the hot brookies with a pinch of sea salt for a sweet and salty contrast.
2. Cool on Tray: Let the brookies cool on the baking tray for about 10 minutes. This allows them to firm up slightly.
3. Transfer to Cooling Rack: Carefully transfer the brookies to a wire rack to cool completely.