Preheat the oven to 350°F (175°C). Grease a 9-inch square baking pan and set aside.
In a small bowl, whisk together the all purpose flour, baking powder, and salt; set aside.
In a medium saucepan over low heat, combine the hot water and 1 tablespoon espresso powder, stirring until dissolved.
Add the granulated sugar and butter to the saucepan and cook, stirring constantly, until the mixture comes to a boil; remove from heat.
Stir in 1 cup semisweet chocolate morsels until the mixture is smooth and chocolate is melted.
Beat in the eggs one at a time, stirring well after each addition until fully incorporated.
Fold the flour mixture into the chocolate mixture until just combined, taking care not to overmix.
Pour the batter into the prepared pan, smoothing the top, and bake for 25 to 30 minutes or until a toothpick inserted near the center comes out with a few moist crumbs.
Cool the brownies completely in the pan on a wire rack.
For the frosting, heat the whipping cream and 1 teaspoon espresso powder in a small saucepan over low heat, stirring until the espresso dissolves and the cream is hot but not boiling.
Remove from heat and add the remaining 1 cup semisweet chocolate morsels, stirring until smooth and melted.
Stir in the powdered sugar until smooth, then refrigerate the frosting until it reaches a spreadable consistency.
Spread the chilled frosting evenly over the cooled brownies, then cut into squares and serve.