Preheat Oven: Preheat your oven to 350°F (175°C) and line a baking sheet with parchment paper.
Mix Dry Ingredients: In a bowl, combine oats, flour, baking soda, and salt.
Mix Wet Ingredients: In a separate bowl, cream together butter, brown sugar, and maple syrup. Add the egg and vanilla extract and mix until smooth.
Combine: Gradually stir the dry ingredients into the wet ingredients. Fold in raisins or chocolate chips, nuts, and seeds if using.
Shape Cookies: Scoop the dough into large spoonfuls onto the prepared baking sheet. Flatten slightly.
Bake: Bake for 12–15 minutes, or until golden brown. Let cool before serving.
