Line an 8X8 square pan with parchment paper, making sure to leave overhang so you can lift the brownies out when they are done
Measure out the chocolate chips and place them in a heat-proof bowl or measuring cup, set aside
In a medium saucepan, add the butter and turn the heat to medium, turn the heat to medium-high, and let the butter foam and sputter until it starts to turn a golden brown. Swirl the pan around making sure to remove the pan from the heat as you see the butter darken to a deeper brown
Pour the browned butter directly over the chocolate chips and let sit for at least 3 minutes. The heat of the butter will melt the chips! Then stir using a spoon or nonstick spatula until the chips and the butter are completely smooth
In a separate large bowl add the granulated sugar, light brown sugar, 3 eggs,1 tsp vanilla extract, and both cocoa powders. Whisk vigorously until the mixture is completely smooth and lightens in color
Add in the browned butter and chocolate mixture and mix until smooth. Add in the brewed Vietnamese coffee. Mix again until combined.
Add in the flour and salt and mix again until smooth
Pour *almost* all of the batter in the pan reserving 1/2 cup of batter on the side (this will be used to swirl in the condensed milk layer)
Once the brownie batter is in the pan, dollop the condensed milk mixture in circles around the surface of the brownies, then dollop the reserved brownie batter on top too. Using a knife swirl the two together by dragging the knife through the batter (see video)
Bake at 325F for 40-45 minutes or until the top is puffed and the center is almost completely set.
Remove from the oven and let cool for 1 hour. Slice and enjoy!