In a small saucepan melt butter over medium heat, swirling pan occasionally until butter starts to turn golden brown and smells nutty, about 8 minutes then pour into another container to cool slightly. For a more detailed explanation of how to prepare, check out our Brown Butter recipe.

Pour browned butter into a large bowl and blend in the sugar, cocoa, vanilla and salt. Add in the eggs one at a time, mixing well after each addition.

Completely mash black beans with a fork, then stir into batter until smooth.

Spread batter into a greased square baking pan, and bake at 375°F for 25-30 minutes.

Allow to cool before cutting into squares.