Layed the slices of 1 large onion on the bottom of the pot. Topped that with leftover pineapple chunks and sprinkled a good pinch of red pepper flakes over. If I had a half a glass of white wine, I'd splash that in, but - I don't. So a few dashes of rice wine vinegar instead... Then I cut the trimmed pork tenderloin/steak into chunks and place on top.
I'm back! Success. Left it on low from 11:30 - 6pm. The smell in the house was making us hungry. I took out the chunks of meat and, using 2 forks, shredded it. Put it back into the pot for a stir in the juices and served it on some simple risotto (only because I'd run out of other rice) and some homemade coleslaw. The flavor was lovely - it was sweet from the pineapple, with just a touch of spice. No added sugar, no added fat. Yum.
One thing: Remove the pineapple chunks before serving. Pork flavored with pineapple is lovely, but pineapple flavored with pork - not so good!