In a medium bowl, whisk together the flour, baking powder, baking soda and salt.
In the bowl of an electric mixer or a large bowl if using a hand mixer, beat the butter until smooth then add the sugars and beat until creamed, about 2 minutes.
Add eggs, peanut butter and vanilla and beat on high until combined. Add the dry ingredients and beat until combined, add oats and beat until combined. Beat in chocolate chips.
Refrigerate for at least 20 minutes. If longer, let it warm up at room temperature for 30 minutes.
Preheat oven to 350º. Line baking sheets with parchment paper.
With an ice cream scoop, scoop out large balls, about 2 tablespoons or more and place on prepared pan about 2 inches apart. Bake for 12-14 minutes, until lightly brown. Allow to cool on baking sheet for a few minutes before transferring to a wire rack.
You can freeze cookies before or after baking. If before baking, you don't need to thaw just add a minute or two to the cooking time.