Preheat your oven to 350°F and line a 9x9-inch square pan with parchment paper.
In a large mixing bowl, use a hand mixer on high to cream together sweetened condensed milk, butter, and sugar until thick and smooth (about 3-5 minutes).
Add the eggs and vanilla extract and mix again to combine.
Next, add the flour, cocoa powder, and salt and mix again until there are no visible clumps.
Transfer batter to your lined pan and pour chocolate chips on top.
Bake for 35-45 minutes and allow to cool completely before slicing and peeling away from parchment paper. Sprinkle on a pinch of salt (optional).
