Favorite Fudgy Brownies

Name: Favorite Fudgy Brownies
Prep time: 15 min
Cook time: 30 min
Total time: 45 min
Cuisine: American
Ingredients: 6 tablespoons unsalted butter ((85g)); 1/4 cup chopped dark chocolate or chocolate chips ((1.5 oz; 43g)); 1 cup granulated sugar ((200g; you can go a little under, but stay above 3/4 cup)); 2 large eggs; 1/4 teaspoon espresso powder ((optional)*); 1 teaspoon pure vanilla extract; 1/2 teaspoon salt; 1/2 cup cocoa powder ((42g)); 1/2 cup all-purpose flour ((63g)); 1/2 cup chocolate chips ((85g)); Coarse sea salt, for sprinkling on top