Homemade Brownies

Name: Homemade Brownies
Cook time: 1 h 50 min
Total time: 1 h 50 min
Cuisine: American
Ingredients: 2 1/4 cups granulated sugar; 1/4 cup brown sugar; 1 tsp. salt; 1 Tbsp. vanilla extract; 1 cup (2 sticks) unsalted butter, plus more for buttering pan; 1 cup chocolate chips; 1 tsp. instant espresso powder (optional); 1 tsp. cinnamon (optional); 1/2 tsp. ground cayenne pepper (optional); 6 large eggs; 1/2 cup vegetable oil; 1 1/3 cups Dutch-process cocoa powder; 1 cup all-purpose flour; 1 tsp. baking powder