A ridged spoon descending from the inside roof of the microwave .Spoon maybe attached using suction cups . Magnets ????Spoon traces patterns in food as bowl rotates off-centre .
rework: A lot of ideas - crankshaft , lazy susan with edge turning by touching inside of microwave and even little motors running on microwaves but for this simple is best .
A suction cupped long flexible spoon that attaches at centre of platter rotation on inside roof . A rollick attached to spoon has a L shaped form that is held ridgid by the weight of dish the spoon is stirring . The rollick is in radius line , on the inside edge of the dish . The dish is smaller than platter and sitting as far out on platter as possible . As the dish/food goes round on the platter the spoon is twisted and the twist releases through the rollick bearing surface stiring the food .
OK not quite a spiral but definitely twisty .-- wjt, Nov 27 2007 The spirograph pen is not stationary. I believe you will find that your suctioned spoon will create nothing more than a spot or circle (depending on the spoon's distance from roof center) in the oatmeal, a bit off-center (depending on the bowl's distance from center).-- globaltourniquet, Nov 27 2007 Circo-stir
MFD while i will burn some more glucose . - and with the magic of time , the edit.-- wjt, Nov 27 2007 random, halfbakery