robert's chocolate cookies (bittersweet) - Lisi's Kitchen

Ingredients

• 6 ounces unsweetened chocolate (Scharffen Berger would be ideal!)
• 5 ounces premium-quality bittersweet chocolate cut into coarse chunks
• 1/3 cup all purpose flour
• 1/4 teaspoon baking powder
• 1/4 teaspoon kosher salt
• 4 tablespoons unsalted butter
• 2 large eggs, room temp
• 1 1/3 cup sugar
• 1/2 teaspoon instant espresso (or 1 1/2 teaspoons finely ground fresh coffee)
• 1 teaspoon vanilla extract
• 1/2 cup toasted walnut pieces (optional)