Line your muffin tin with liners or use a silicone pan. I used liners in a metal pan, it was easy to lift in and out of the fridge.
Heat your butter in a pan on medium heat on your stove.
Remove your pan from the burner and stir in the peanut butter, graham crackers, powdered sugar, and salt.
Continue to stir until well mixed, the mixture will be lumpy depending on how fine your graham cracker crumbs are.
Use a cookie scoop and disperse the peanut butter mixture into the liners.
Place the muffin tray in the fridge to allow them to start to cool.
In a microwavable bowl or Pyrex measuring glass melt chocolate chips slowly in the microwave in a bowl. Do ten-second intervals until melted and smooth.
Pull out the muffin pan and spoon the chocolate on top.
Put back in the fridge for about 45 minutes until set!