Preheat Oven: Preheat to 350°F (175°C). Line baking sheets with parchment paper.
Mix Wet Ingredients: In a bowl, cream butter, peanut butter, granulated sugar, and brown sugar until smooth. Beat in the egg and vanilla extract.
Combine Dry Ingredients: In another bowl, whisk together flour, baking soda, and salt. Gradually add to the wet mixture. Stir in oats and chocolate chips.
Shape Cookies: Scoop large spoonfuls of dough (about 2 tablespoons) onto prepared baking sheets, spacing them 2 inches apart.
Bake: Bake for 10-12 minutes or until edges are lightly golden. Let cookies cool on the baking sheet for 5 minutes, then transfer to a wire rack.
