Pre-heat your oven to 400F.
In a bowl, beat the eggs, add the condensed milk and vanilla extract. Incorporate thoroughly.
In a small pan, melt the butter and chocolate chips together.
In another bowl, put all your dry ingredients: all-purpose flour, cocoa powder, and salt.
Gradually, add them to the previsous mixture and stir until smooth.
Add some walnuts, pecans, or any other nuts of your choice. (Optional)
Take a 8 x 8 inch baking dish, layer some parchment paper at the bottom. Fold in the angles so it stays put.
Pour in your batter and bake in the oven for 18-20 minutes.
Allow to cool before enjoying!