Melt the chocolate chips with the coconut oil in 30 second increments in the microwave until smooth, for about 90 seconds total

Pour the melted chocolate into a large bowl and add in the peanut butter. Stir the chocolate and peanut butter together with a whisk until smooth

Add in the rice crispy cereal and chopped peanuts. Toss together until evenly incorporated

Transfer the mixture into a parchment lined 8 x 8 or 9 x 9 dish. Flatten it into the pan using a rubber spatula or back of a spoon

Freeze for at least 1 hour to harden. Remove from freezer and cut twice down and five times across to make 18 bars. Top with flakey sea salt if desired

Keep stored in an air tight container or ziplock bag in the freezer for up to 2 months