Brownies with espresso

Preheat the oven to 180°C (350°F). Melt the butter and chocolate over a double boiler. Let cool. Sift the flour, cocoa powder, and pinch of salt into a bowl and mix. In another bowl, beat the sugar and eggs together until light and frothy. Add the vanilla extract and double espresso to the egg mixture and beat briefly. Fold the cooled chocolate-butter mixture into the egg mixture until a homogeneous mass is formed. Then fold in the flour-cocoa mixture until everything is combined. Pour the batter into a greased baking pan. Bake the brownies for about 25 to 30 minutes. The top should have a light crust, but the inside should still be a bit moist. Test with a toothpick; it should come out clean with a few moist crumbs clinging to it. Let the brownies cool completely and cut into squares.