In a large mixing bowl, combine the rolled oats, peanut butter, honey (or maple syrup), and vanilla extract. Stir until everything is well mixed and forms a sticky consistency.
Add the mini chocolate chips and chopped nuts to the mixture, and fold gently to combine evenly.
Line a muffin tin with paper liners or lightly grease it with cooking spray.
Using your hands or a spoon, scoop the mixture into each muffin cup, pressing down firmly to pack them tightly.
Once all the mixture is in the muffin tin, place the tin in the refrigerator for at least 30 minutes to allow the cups to set.
After the chilling time, remove the cups from the muffin tin and optionally sprinkle a pinch of sea salt on top for an added flavor kick.
Notes
Serve on a decorative plate and garnish with extra chocolate chips or nuts for visual appeal.