Preheat the oven to 350°F (175°C). Line an 8x8 inch baking pan with parchment paper.
In a mixing bowl, melt the 1 cup of butter for the brownie layer. Once melted, mix in the granulated sugar until well combined.
Add the eggs, one at a time, mixing well after each addition. Stir in the vanilla extract.
In another bowl, whisk together the flour, cocoa powder, salt, and baking powder. Gradually add the dry ingredients to the wet mixture until just combined.
Pour the brownie batter into the prepared baking pan, spreading it evenly. Bake for 20 minutes or until a toothpick comes out with a few moist crumbs. Let cool completely in the pan.
In a mixing bowl, beat together the softened butter and brown sugar for the cookie dough filling until creamy. Mix in the vanilla extract.
Gradually add the flour and salt, mixing until well combined. Stir in the chocolate chips. If the dough is too crumbly, add milk a tablespoon at a time until the dough holds together.
Once the brownies have cooled, cut them into 12 equal squares. Take one brownie square and flatten it slightly in your hands. Place a spoonful of cookie dough in the center and wrap the brownie around the dough, rolling it into a ball.
Repeat the process with all brownie squares and cookie dough, placing the filled brownie bombs on a baking sheet lined with parchment paper.
In a microwave-safe bowl, melt the chocolate chips with the coconut oil (if using) in 30-second increments, stirring between each, until smooth.
Dip each brownie bomb into the melted chocolate, ensuring they are well-coated. Place them back on the baking sheet and allow the chocolate to set.
Once the chocolate is firm, your Chocolate Chip Cookie Dough Brownie Bombs are ready to enjoy!