Line the pan with parchment paper before starting.
In a non-stick pot on medium-low heat, add the butter. Once the butter melts and starts to brown slightly, add in the marshmallows and pistachio butter. Mix the butter, pistachio butter and marshmallows well until they are completely combined before adding in any other ingredient.
Once combined turn off the heat, add in the Rice Krispie cereal and chopped pistachios. When almost mixed in with the marshmallows, add in the extra marshmallows and the chocolate chips. At this point it'll start cooling down quickly and it'll be harder to mix.
Once they are combined enough, transfer to the pan and press them down slightly in the pan until the pan is full. You may have a little extra leftover, enjoy it.
Allow the rice krispie treats to cool then using the parchment paper, lift them out of the pan. Slice them up into squares and enjoy.