Preheat oven to 350°F. Line a baking sheet with parchment paper and set aside.
In the bowl of your stand mixer fitted with the paddle attachment mix together the peanut butter and both sugars on medium speed until combined and creamy.
Add in the egg and baking soda and mix on medium until smooth.
Scoop out about 2 TBS. of dough and roll into balls. Place the dough balls onto the prepared baking sheet. You can leave them to bake just like that or you can use a fork to press the dough down creating a crisscross pattern.
Bake for 9-10 minutes or until the cookies are set at the edges.
Allow the cookies to cool on the baking sheet for 3-4 minutes before transferring to a wire rack to cool completely.
While cookies are cooling, melt 4 TBS. dark chocolate chips with 1 tsp. of coconut oil in a small saucepan.
With a spoon, drizzle chocolate across the cookie, back and forth.