Espresso Biscotti

Name: Espresso Biscotti
Prep time: 15 min
Total time: 15 min
Cuisine: American, Italian
Ingredients: 1/2 c. unsalted butter; 1/2 c. granulated sugar; 1/2 c. packed light brown sugar; 3 large eggs, room temperature and divided; 2 tsp. vanilla extract; 3 c. all-purpose flour; 2 tbsp. espresso powder or instant coffee; 1 1/2 tsp. baking powder; 1/4 tsp. kosher salt; 2 (4-oz.) 60% bittersweet chocolate bars, chopped; 2 oz. white chocolate, chopped