• Preheat oven to 350° F. Line a 9x9-inch pan with parchment paper and spray with nonstick cooking spray.

To Prepare Brownies

• In a medium bowl, sift flour, baking powder and salt and set aside.
• Use a double boiler or a heatproof bowl set over a pan of simmering water (water from either should not actually touch inserted pan).
• Combine butter, chocolate chips and espresso powder in top unit and stir until melted and smooth. Remove from heat and let cool down.
• Beat sugar, eggs and 1/2 cup Kahlua in mixer. Pour in chocolate mixture and beat well. Mix in dry ingredients and beat until just combined.
• Add 3/4 cup toasted walnuts and stir into brownie dough.
• Pour batter into prepared pan.
• Bake for 40 to 45 minutes until toothpick inserted in center comes out almost clean (slightly gooey is fine; these are not cake brownies!). Top may be slightly cracked.
• Remove brownies from oven and immediately brush the top of the warm brownies with 2 Tbsp of Kahlua. Let brownies cool completely.

To Prepare Icing

• Brown butter in saucepan. Remove from heat and add Kahlua & whipping cream. Whisk in powdered sugar until you have a smooth but still pourable consistency.
• Pour on top of cooled brownies and spread to edges to cover completely.
• Sprinkle with 1/4 cup of reserved toasted walnuts; light press nuts into frosting.Refrigerate until set (chilled brownies are easier to cut. Use a large, sharp knife that is warmed in a glass of hot water; wipe clean after each cut).
• Store brownies in a covered container; best if eaten within a couple of days.