Sweet Potato Stew

Mark Bittman of the Times offered a selection of vegan dishes to ring in the new year this Sunday.  Having a cache of sweet potatoes, we made a version of his sweet potato stew, and it was delicious.
Take two medium size sweet potatoes (about 1 pound) and cut into 1/2 inch dice.  Cut up a large onion in fine dice.  Sauté the onion in some vegetable oil in a casserole until the onion is pretty soft, then add the sweet potatoes, a large knob of chopped ginger, a couple of sliced serrano peppers (leave the seeds in and it's very hot!), and a heaping teaspoon of curry powder.  Meanwhile, cut an apple into medium dice and reserve.
After the sweet potato and onions and the other ingredients have cooked together for a bit, add some coconut milk thinned with water or stock. (We used duck stock because it was on end -- end of vegan story).  Pour in the liquid so it comes either halfway (Bittman) or almost to cover (us) the sweet potato mixture, and simmer until the sweet potatoes are cooked and soft, stirring from time to time.  Mash up half of the potatoes with a masher, and add the apple.  Warm through.
The original recipe called for a garnish of cilantro and peanuts.  We didn't have peanuts, so stirred in a heaping tablespoon of peanut butter into the sauce, and topped with chopped cilantro.
Excellent!  But no pictures.