Preheat oven to 350F (175C) and line a 9x9" (23x23cm) baking pan with parchment paper.

Combine butter pieces and chopped chocolate in a medium-sized heatproof bowl and heat in the microwave in 25-second increments, stirring in between, until melted and smooth.

Add cocoa powder, sugars, eggs, vanilla, instant coffee (if using), and salt and stir until well-combined.

Add flour and stir well. If using chocolate chips, stir these in now.

Spread batter evenly into prepared baking dish and bake for 30-35 minutes or until a toothpick inserted in the center comes out clean or with fudgy crumbs.

Allow to cool before preparing cookie dough topping.

Spread flour in an even layer over parchment paper on a cookie sheet and bake for 7 minutes or until the temperature of flour reaches at least 160F (71C). Allow flour to cool.

In a separate bowl, beat together butter, sugars, vanilla extract, and salt using an electric mixer.

Sift the cooled baked flour over the butter mixture and beat until all flour is absorbed. Add 1-2 Tablespoons of milk or cream as needed if the mixture is dry.

Stir in mini chocolate chips.

Spread cookie dough evenly over the cooled brownie layer.

Combine chocolate chips and shortening in a heatproof bowl. Heat in the microwave in 20-25 second increments, stirring in between, until melted and cooled.

Pour chocolate over the cookie dough layer and spread evenly. Allow chocolate to cool until set before cutting and serving.