Thick, chewy, and deeply chocolatey, these double chocolate brownies are a homemade version of the iconic Starbucks treat — with melty chocolate in every bite.
1/2 cup (1 stick) unsalted butter
4 oz dark chocolate (60–70%), chopped
3/4 cup granulated sugar
1/4 cup brown sugar
2 large eggs + 1 egg yolk
1 tsp vanilla extract
1/2 cup all-purpose flour
1/4 cup Dutch-processed cocoa powder
1/4 tsp salt
1/2 cup chocolate chips or chunks
Preheat oven to 325°F (163°C). Line and grease an 8×8-inch baking pan.
Melt butter and dark chocolate together; let cool.
In a bowl, whisk eggs, yolk, and both sugars until light and thick (2–3 min).
Add vanilla and melted chocolate mixture; whisk until smooth.
Sift in flour, cocoa powder, and salt. Fold until just combined.
Stir in chocolate chips, reserving a few for topping.
Spread batter into pan, top with extra chips, and bake 30–35 minutes.
Cool completely, chill for clean cuts, then slice and serve.
Store at room temp for 4 days or freeze for 2 months. Add espresso or nuts for variation.