Preheat oven to 350°F. Spray a standard-sized muffin tin with cooking spray.

In a medium bowl mix the butter, sugar, vanilla, egg, coffee together until smooth. In a small bowl whisk together the cocoa powder, flour, baking powder, and salt. Add the dry ingredients to the wet ones and stir just until combined. Fold in the chocolate chips.

Fill the muffin cups about 1/2 way with the batter (you'll have enough batter to fill 4-6 of the cups). Add about a tablespoon of water to the empty cups. Bake the brownies for about 20 minutes or until a toothpick comes out clean. Allow them to cool on a wire rack. Once cooled, chop them up into bite-sized pieces.

Melt the sugar in a medium pot over medium-high heat, stirring constantly. Once the sugar has melted let it come to a boil and stop stirring. Once the sugar turns to an amber color (it won't take long) add the butter and whisk it all together until the butter is melted.

Once the butter is melted, remove the pot from the heat and slowly pour in the heavy cream. Whisk continuously (be careful - the cream will bubble up) until the cream is incorporated and the sauce is smooth. Let it cool for a few minutes and then transfer it to a glass container.

In a large bowl stir together the sweetened condensed milk and vanilla.

In a separate bowl (or stand mixer) whip the heavy cream until you get soft peaks. Gently fold the whipped cream into the condensed milk and vanilla mixture until combined. Gently fold in the chopped brownies. Pour the ice cream mixture into a 9x13 baking dish. Using a spoon swirl 1/2 of the caramel sauce in the ice cream (see notes). Cover the dish and place in the freezer for at least 6 hours or until the ice cream is set.