Preheat the oven to 350 F. Grease an eight or 9-inch baking pan or line with parchment paper and keep this aside.
Add butter, sugar, cocoa powder, and coffee powder in a large microwave-safe bowl. Heat this for 30 seconds. Stir and heat for another 30 seconds or until butter is melted completely and well combined with other ingredients.
½ cup + 2 tablespoon Butter, 1 cup Sugar, ½ cup Cocoa powder, 1 teaspoon Instant coffee powder
Add vanilla, salt, and milk to this and stir until combined.
1 teaspoon Vanilla extract, ¼ teaspoon Salt, ¼ cup Milk
Finally, add the flour, pinch of baking powder and mix until combined. Do not overmix.
½ cup Flour, Pinch of baking powder
Spread the brownie batter to the prepared baking pan.
Add dollops of Sesame or nut butter and swirl them in the brownie batter using a knife.
⅓ cup Nut butter or Sesame Spread or any spread of your choice
Bake for 32 to 35 minutes. The toothpick inserted will have some moist crumbs.
Let the brownies cool in the pan for 10 minutes. Then, remove it from the pan.
Once it cools down, slice and serve as needed.
These brownies remain fresh outside when stored in an airtight container for 4 to 5 days, a few weeks in the refrigerator, and several months in a freezer.