Preheat oven to 350 degrees and line a loaf pan with parchment paper or aluminum foil.

Melt butter in a small dish in the microwave and set aside to cool slightly.

¼ cup unsalted butter, melted and set aside

In a medium bowl, whisk together the flour, sugar, cocoa powder, sea salt, and baking powder.

⅓ cup flour,½ cup sugar,2 TBS + 2 tsp unsweetened cocoa powder,⅛ tsp sea salt,⅛ tsp baking powder

Add egg and vanilla and stir.

1 egg,1 tsp vanilla extract

Add melted butter and mix until smooth.

Fold in melted chocolate and stir until just combined.

¼ cup milk chocolate chips, melted smooth

Pour batter into a prepared loaf pan and bake for 20-22 minutes, rotating halfway through. Brownies will puff up slightly as they bake, but the top will fall when they are done.

Allow brownies to cool in the pan for 15-30 minutes. Lift out of the pan, slice, and serve.

Store brownies in an airtight container for 3-4 days or freeze.