In a large bowl, whisk together the oats, baking powder, baking soda, cinnamon, and salt.
In a medium bowl, combine the peanut butter, egg, vanilla, and honey. Whisk until blended.
Scrape the liquid mixture into the oat mixture and stir just until combined. The dough will be wet and sticky. Fold in the chocolate chips. Place in the refrigerator and let chill for at least 30 minutes or up to 3 days.
When ready to bake, place a rack in the center of your oven and preheat the oven to 350 degrees F. Line a large rimmed baking sheet with parchment paper or a silicone baking sheet. Remove the dough from the refrigerator (if it is very stiff, you may need to let it sit out for 5 to 10 minutes). With a cookie scoop or spoon, drop the dough into 2-inch balls and arrange on the baking sheet, leaving 1 inch of space around each. With your fingers, gently flatten each cookie to be about 3/4-inch thick.
Bake until the cookies are golden and firm around the edges and set on top, about 9 to 10 minutes. Place the baking sheet on a wire rack and let the cookies cool on the baking sheet for 2 minutes, then transfer the cookies to the rack to cool completely.
*I prefer quick oats for the most soft, chewy cookies. Rolled oats will also work, but the cookies will just have a heartier texture. Do not use steel cut oats or instant oatmeal. To make your own quick cooking oats: pulse rolled oats in the food processor 3 or 4 times to lightly break them up (do not pulse all the way into a flour).
TO STORE: Store leftover cookies an airtight storage container at room temperature for up to 3 days or in the refrigerator for up to 5 days.
TO FREEZE: Place cookies in an airtight freezer-safe storage container in the freezer for up to 3 months.
TO MAKE GLUTEN FREE: If you are making this cookie for someone who cannot tolerate gluten, be sure your oats are certified gluten free.
TO MAKE VEGAN: Use maple syrup instead of honey. For the egg: I haven’t tried this with a flax egg instead of the regular egg yet, but I’d love to hear how it goes if someone does play around!