Mix it all but the marshmallows in the measuring cup, microwave it for ~2 minutes, cool it for 5-10 minutes in the fridge so it thickens, and it’ll make about 12 cookies (I cheated like a mad bastard and used my new cookie scoop, because I have one of those now). ~15 m @ 175C/350F and add the marshmallows about 5 minutes in.
They’ve still got less sugar than the average oatmeal raisin cookie, even with the mini marshmallows. And they’re chocolate. And the cleanup pretty much consists of washing a measuring cup, the cookie scoop, and a butter knife and tossing out the foil from the baking pan. I cook tasty things, yes, but I am a lazy bastard. Maximum result for minimal effort.