Preheat the oven to 350°F. Spray an 8x8-inch baking pan with nonstick spray or line with a piece of parchment paper with 2 inches on each side for easy lift after baking. Set aside.
In a medium saucepan, melt the butter with ½ cup of chocolate chips and the espresso or coffee.
¼ cup salted butter, 1½ cups milk chocolate chips, ¼ cup brewed black coffee or espresso
Once the butter and chocolate have melted, remove the pan from heat. Whisk in the eggs and sugars. Gradually mix in the flour and stir until it becomes a semi-thick batter. Let the batter cool for a minute and then stir in the remaining 1 cup of chocolate chips, until they are evenly mixed into the batter.
2 large eggs, 1 cup granulated sugar, ¼ cup brown sugar, ¾ cup all-purpose flour
Top with extra chocolate chips (optional). Pour the brownie batter into the prepared pan and bake for 25-30 minutes. Remove from the oven and allow brownies to cool before cutting or frosting.
¼ cup chocolate chips
Chocolate Chips: I sprinkled additional chocolate chips on top before baking. There are also espresso flavored chips you can use for additional coffee flavor.
For richer flavor, use espresso instead of coffee.
Don't add the chocolate chips to the batter when it's too warm. If you do, the chocolate chips will most likely melt and not hold their shape.
Dark brown sugar will deepen the overall flavor of the brownies more than light brown sugar.
Storage: Store espresso brownies in an airtight container at room temperature for up to 3 days, in the refrigerator for up to 5 days, or in the freezer for up to 3 months.