Preheat the oven to 350 degrees Fahrenheit.
Add the butter, peanut butter, white sugar, and brown sugar to a large mixing bowl. Whisk until everything is completely combined.
Add the egg and vanilla extract and mix again until combined.
Stir in the sourdough discard until incorporated.
In a separate mixing bowl whisk together the flour, oats, salt, and baking soda. Add the dry ingredients into the wet ingredients and use a spatula to begin to fold everything in.
Once the mixture is mostly incorporated, add the chocolate chips and chocolate candies. Continue to mix until everything is combined.
Take about ¼ cup of the dough per cookie and form dough balls. Use your hands to press the ball down lightly to form a disc. Place onto a parchment paper lined baking sheet and bake for 10-11 minutes or until the outside is lightly browned and still slightly soft in the center.
Let the cookies cool on the baking sheet for about 5 minutes, then transfer to a wire cooling rack to cool completely before enjoying.
