In a mixing bowl, combine the oats, protein powder, coconut, and chocolate chips.
Add the peanut butter, honey, and vanilla extract. Stir well until fully combined. If the mixture is too dry, add a tablespoon of milk at a time until it comes together.
Roll the mixture into small balls, about 1 inch in diameter.
Place the balls on a baking sheet or plate and refrigerate for at least 30 minutes to firm up.
Store in an airtight container in the fridge for up to a week—or freeze for longer shelf life.