Preheat oven to 350 degrees F. Liberally grease two 9" springform pans with cooking spray. Place a parchment circle in the bottom of each pan, and spray that with more cooking spray. Seriously, you cannot use enough cooking spray here! Set aside.
In two large bowls, prepare each box of brownie mix according to package directions. Pour each bowl of batter into each springform pan. Bake for approximately 30-35 minutes or until a toothpick inserted near the center comes out with clean or moist, not wet, crumbs. Cool completely before releasing the outer rim of the pan.
Once brownie "cake" layers have cooled, make your cookie dough. In the bowl of a stand mixer, beat together the butter, brown sugar and sugar until combined, about 1 minute. Add in the heavy cream and vanilla, beating well. Lastly, add in the flour and beat until combined. Fold in the semi-sweet chocolate chips.
Place one brownie "cake" layer upside down onto a cake stand or serving plate. Spread the cookie dough in a thick, even layer on the brownie layer. Top with the second brownie layer, right side up.
In a medium microwaveable bowl, add in the 1 cup of semi-sweet chocolate chips and the heavy cream. Microwave on HIGH power for about 30 seconds. Stir until smooth and glossy. Pour the ganache over the top of the cake and let it drip down the sides. Sprinkle with the miniature chocolate chips. Store covered in the fridge for 3 days or at room temperature, covered, for about 1 day.