I used one of the chocolate bars we were given when we visited Manos de Cacao to make single origin brownies. I only had 2 oz of the chocolate, so I made the batter with neutral flavor cocoa powder then chopped the chocolate into it. This is their Comalcalo bar (an area in Tobasco, Mexico, between Chiapas and the Southernmost part of the Gulf Coast), which has tannic, fruity raisin-like notes which should give the brownies surprise bits of tang.

All purpose flour, for preparing pan
4 large eggs
1 cup sugar
3/4 cup brown sugar
8 ounces butter, melted
1 1/2 cups cocoa powder
2 tablespoons chocolate liquor
1 teaspoon vanilla extract
1/2 cup all purpose flour
1/4 teaspoon salt
2 ounces single origin chocolate, chopped

Preheat the oven to 350 degrees F. Grease an 9×7-inch baking pan. Pour a small amount of flour into the pan and knock to coat the surface with flour. Discard extra.

Beat the eggs in a stand mixer until fluffy. Add the sugar and brown sugar. Beat until combined. Add the butter, cocoa powder, chocolate liquor, vanilla, flour and salt. Beat until well combined. Stir in the single origin chocolate.

Pour the batter into the prepared pan and bake for 45 minutes or until a toothpick inserted into the center of the brownies comes out clean. Allow to cool completely on a wire rack before cutting.