01 -
Set the oven to 350°F and line a 9x9 pan using parchment paper.
02 -
Melt the butter along with about 1 1/2 cups of the chocolate chips. Stir in the sugar, vanilla, and liqueur.
03 -
Whisk the eggs until slightly foamy, and then mix them into the melted chocolate.
04 -
Blend together the flour, cocoa, baking powder, and salt. Toss in the leftover chocolate chips.
05 -
Pour half the mixture into the pan and bake for 20 minutes.
06 -
Layer the marshmallows on top, then broil for 1-3 minutes until they turn golden.
07 -
Spread the rest of the batter over the marshmallows, sprinkle with dark chocolate chunks, and bake again for another 20 minutes.
08 -
Leave the pan to cool for 20 minutes before slicing into pieces.