Can I use creamy peanut butter instead of peanut butter chips for easy microwave peanut butter fudge with sweetened condensed milk?
Possibly, but probably not. Peanut butter chips are made from partially defatted peanut powder (the stuff that’s left behind after squeezing out peanut oil from peanuts) combined with hydrogenated oils which are solid at room temperature. If you substituted peanut butter (without the hydrogenated oils), the result might not thicken properly when cooled.
If you try this out, also keep in mind that peanut butter is denser than a pile of peanut butter chips. Measure by weight, or just eyeball it and use 2/3 or so as much.