Method

1. Preheat oven to 180 degrees.
2. Grease an 8-inch square pan dusting it with flour and line with parchment paper.
3. In a bowl, add all-purpose flour, cocoa powder, salt and baking powder; mix it and keep aside.
4. Place a heatproof bowl with the butter inside over a pan of simmering water and let it melt.
5. Remove the bowl and stir in the coffee powder, chopped chocolate and stir till chocolate melts completely.
6. Whisk in eggs and add the vanilla essence before adding the sugar. Mix well.
7. Now add in the flour-cocoa powder mixture until no trace of flour is left, using a wooden spoon.
8. Pour the batter into a greased pan and bake in a preheated oven at 180 degrees for 35-40 minutes until a toothpick inserted in the centre comes out with a few moist crumbs attached.
9. Cool it on a wire rack for 30 minutes and cut into squares.
10. Store in an airtight container.