Cut the top half off of the muffin cups so that they are shallower.
Reserve 1/4 cup of the chopped chocolate. Pour the rest into a glass bowl and melt them in the microwave: Microwave at 50 percent power for 1 minute. Stir the chips gently, and let them sit for a minute or so. If the chocolate needs more melting, microwave those chippies again at half power for 30 seconds. Stir gently. Continue the process, stirring gently as you go. But be very careful not to overcook the chocolate.
Temper the melted chocolate by stirring in the reserved 1/4 cup of chopped chocolate chips as it cools. This will 're-emulsify' the chocolate and enable it to harden at room temperature.
Using a teaspoon, spoon a portion of the chocolate into the middle of a muffin cup. Draw the chocolate up the edges of the cup with the back of the spoon (or you can paint the chocolate on with a small paintbrush). Coat the entire inside of the muffin cup with chocolate and place it into a muffin tin. Repeat with the remaining muffin cups and then put the whole muffin tin in the refrigerator so that the chocolate hardens.
Combine the peanut butter, powdered sugar, and salt in a mixer. Pour the mixture into a resealable plastic bag and seal.
When the chocolate in the muffin cups has hardened, pop the sweetened peanut butter into the microwave on full power for 1 minute. This will soften up the peanut butter so that it easily flows into the cups.
Cut a corner off the edge of the plastic bag. You can use this to pipe the peanut butter into each of the chocolate-coated cups. Put a banana chip on top of each cup. Put the candy in the refrigerator to harden the peanut butter. This should take 15 to 20 minutes.
Recipe courtesy of Michael Chiarello