We're all big kids when it comes to Rice Crispy Squares. And when peanut butter (or any nut butter) and chocolate chips join in, well who can say no!!
Set a large pot over low heat on the stove. Melt the butter. Once the butter has melted add in the peanut butter and stir to completely soften the peanut butter. Then take the veggie spray and spray the sides of the pot as well.
Once the marshmallows are JUST melted, remove the pot from the heat. Stir in the cereal and salt until just combined. Add in the remaining 2 cups of mini marshmallows. Stir them through roughly, and then add the 1/2 cup of chocolate chips and give it all a few more good stirs to get the chocolate spread around.
Spoon the mixture into the prepared pan. Spray your hands and push down gently and evenly. Avoid pushing down too far, this will result is a dense and tough square. Take the remaining chocolate chips and the flaked salt and sprinkle these evenly over the top. If you want, you can tap them down, but they may start melting depending on how warm the top still is. Be careful. Maybe leave well enough alone!
Store in a sealed container for three days. Do not freeze, they will be hard even when thawed.