Step 1

Melt the chocolate and the butter in a glass bowl placed over simmering water.

Step 2

Once melted, remove the bowl from the simmering water, stir in the sugar and then the eggs, one by one, into the melted chocolate and butter, mixing after each addition.

Step 3

Next, mix in the cocoa powder and a pinch of salt.

Step 4

Lastly, stir in the all-purpose flour, making sure it's well incorporated.

Step 5

Pour the batter into an 8x8-inch (20x20cm) pan that you've buttered and then lined with parchment paper (the bottom and the sides).

Step 6

Bake in a 350°F/180°C oven for 35-40 mins.

Step 7

Once baked, let it cool completely, then take it out of the cake pan, remove the parchment paper, and cut into nine squares, wiping the knife with a cloth before cutting each time (dip the knife in hot water before cutting and then wipe it with a cloth).