Preheat oven 350F & line an 8x8 baking pan with parchment paper.
Melt the unsalted butter & chocolate in a heat safe bowl over a small pot of simmering hot water.
Stir frequently until fully melted, silky, & smooth. Remove bowl from the heat & set aside.
In a large mixing bowl, combine the eggs & light brown sugar with a spatula until fully combined & sugar is fully mixed in.
Pour the melted butter chocolate mixture into the egg mixture, & mix again with spatula until combined.
Add the flour, baking powder, & unsweetened cocoa powder, semi sweet chips to the wet ingredients, & gently fold until just combined. Do not overmix.
Pour brownie batter into prepared baking pan & bake for 23-25 minutes. Cool on counter until room temperature.
Whip the mascarpone cream with an electric mixer until creamy.
Add the heavy cream, vanilla, & powdered sugar to mascarpone cream & whip until smooth & thick.
Dip each lady finger into the coffee, layer them onto the brownies single layer.
Spread mascarpone cream evenly over top of the soaked lady fingers, & dust with cocoa powder.
Chill in fridge for atleast 1 hour before serving.
