Ingredients

• 0.5 cup unsalted butter
• 4 ounce unsweetened chocolate, chopped
• 1 cup granulated sugar
• 2 eggs
• 1 teaspoon vanilla extract
• 0.75 cup all-purpose flour
• 0.25 cup unsweetened cocoa powder
• 0.5 teaspoon baking powder
• 0.5 teaspoon salt

Steps

1. Preheat oven to 350°F (175°C). Line a 9x9 inch baking pan with parchment paper, allowing edges to overhang for easy removal.
2. In a medium saucepan over low heat, combine butter and chopped unsweetened chocolate. Stir frequently until completely melted and smooth, about 3–4 minutes.
3. Remove the saucepan from heat and stir in granulated sugar until combined.
4. Add the eggs one at a time, stirring well after each addition. Stir in vanilla extract.
5. In a separate bowl, whisk together flour, cocoa powder, baking powder, and salt.
6. Fold the dry ingredients into the wet ingredients using a spatula until just combined. Do not overmix; a few streaks of flour are acceptable.
7. Pour the batter into the prepared baking pan and spread evenly to the corners.
8. Bake for 25–28 minutes, or until a toothpick inserted in the center comes out with a few moist crumbs still attached (do not overbake).
9. Remove from oven and allow to cool in the pan for 15 minutes, then lift out using the parchment overhang and transfer to a wire rack to cool completely, about 30 minutes.
10. Cut into 12 equal squares (3 rows by 4 columns) using a sharp knife, wiping the blade between cuts for clean edges.