Preheat oven to 350ºF.
In small bowl, mix together the oats and baking soda; set aside.
In a large bowl, beat peanut butter, brown sugar, eggs and vanilla with an electric mixer until smooth, about 3 minutes. Mix in dry ingredients with a wooden spoon, then gently fold in chocolate chips.
Roll cookies into 2-inch dough balls and place onto cookie sheet 2 inches apart, then barely flatten the top of the cookie with your hand. The dough should be pretty sticky so if you find this method annoying, simply use a cookie scoop to drop the cookie dough onto the prepared baking sheet. The cookies may not be as round in shape and perhaps a bit thicker, but that’s okay, they will still be delicious.
Bake cookies for 9-11 minutes and remove when edges barely begin to turn a golden brown. The cookies may look a little underdone, but they will continue to cook once you remove them from the oven. Cool for 2 minutes on the cookie sheet then transfer to a wire rack to cool completely. Repeat with remaining cookie dough.
Makes 16-20 cookies.
