1 cup semi-sweet chocolate chips or chopped chocolate
1 tablespoon cocoa powder
1 cup granulated sugar
½ teaspoon vanilla extract
1 cup all-purpose flour
¼ teaspoon salt
Preheat oven to 400°F and line a rectangular cake pan with parchment paper.
In a saucepan with a double boiler, melt butter and unsweetened chocolate together over low heat. Stir with a wooden spoon until just melted. Remove from heat and allow to cool a few minutes.
Beat eggs with sugar vigorously until white. Add vanilla extract.
Add melted chocolate, flour, cocoa powder and salt. Stir until better is smooth.
Pour into the lined cake pan and transfer to the oven. Bake for 25-30 minutes, until crisp on the outside, but still soft in the inside. Remove from oven and allow to cool for a few minutes before popping them in the freezer for 10 or 15 minutes. Slice with a sharp knife, cleaning the knife off between slices, and enjoy!