Preheat your oven to 350°F (175°C). Gather all your ingredients and equipment.

In a mixing bowl, cream the softened unsalted butter, brown sugar, and granulated sugar until light and fluffy (about 3-4 minutes).

Add eggs one at a time, mixing until fully incorporated before adding the next.

In a separate bowl, whisk together all-purpose flour, baking powder, baking soda, and pinch of salt. Gradually mix into the wet ingredients.

Fold in the rolled oats, chocolate chips, and chopped pecans using a spatula until evenly combined.

Line a baking sheet with parchment paper. Drop heaping mounds of cookie dough onto the sheet with space between each mound.

Bake in the preheated oven for 9-11 minutes, until the edges are set and centers are slightly soft.

Remove from the oven and let cool on the baking sheet for 5 minutes before transferring to a wire rack.