Most indulgent brownies

1 pound unsalted butter
1 pound plus 12 ounces semisweet chocolate chips, divided
6 ounces unsweetened chocolate
6 extra-large eggs
3 tablespoons instant coffee powder
2 tablespoons real vanilla extract
2 1/4 cups sugar
1 1/4 cups all-purpose flour, divided (1 cup for batter and 1/4 cup in the chips and nuts)
1 tablespoon baking powder
1 teaspoon kosher salt
Melt together butter, 1 pound of semisweet chocolate chips, and unsweetened chocolate and set aside.
Stir together eggs, coffee, vanilla and sugar. Add in the chocolate and butter mixture.
Mix together one cup of the flour, baking powder and salt. Mix in the chocolate mixture.
Stir together remaining chocolate chips with remaining flour, once they are fully coated, add into the batter, stirring gently.
Bake in a 9x13 pan for 30 minutes at 350 degrees. DO NOT OVER COOK. I actually liked them a tiny bit undercooked.