Line a baking sheet with parchment paper.
Peel and slice the bananas into 1/2-inch thick rounds.
Spread a small amount of peanut butter on top of each banana slice.
Press a few chopped peanuts into the peanut butter layer.
Place the baking sheet in the freezer for 1 hour or until firm.
In a microwave-safe bowl, combine dark chocolate chips and coconut oil, heating in 30-second intervals until smooth.
Remove bananas from freezer and dip each slice into the melted chocolate to coat.
Return the coated slices to the parchment paper and freeze for an additional 1 hour until the chocolate is set.