Preparation Put oven racks in upper and lower thirds of oven and preheat oven to 375°F. Whisk together flour, baking soda, and salt in a small bowl. Beat together butter, sugars, and vanilla in a medium bowl with an electric mixer at high speed until pale and fluffy, about 3 minutes, then beat in egg until combined well. Reduce speed to low, then add flour mixture and mix until just combined. Stir in granola and chocolate chips. Drop 18 mounds (about 2 level tablespoons per mound) of batter about 2 inches apart onto 2 ungreased large baking sheets, then pat each mound into a 2 1/2-inch round. Bake cookies, switching position of sheets halfway through baking, until pale golden, about 13 minutes. Cool on sheets 1 minute, then transfer to racks to cool completely.
Preparation Put oven racks in upper and lower thirds of oven and preheat oven to 375°F. Whisk together flour, baking soda, and salt in a small bowl. Beat together butter, sugars, and vanilla in a medium bowl with an electric mixer at high speed until pale and fluffy, about 3 minutes, then beat in egg until combined well. Reduce speed to low, then add flour mixture and mix until just combined. Stir in granola and chocolate chips. Drop 18 mounds (about 2 level tablespoons per mound) of batter about 2 inches apart onto 2 ungreased large baking sheets, then pat each mound into a 2 1/2-inch round. Bake cookies, switching position of sheets halfway through baking, until pale golden, about 13 minutes. Cool on sheets 1 minute, then transfer to racks to cool completely.