I've not tried it in a crock pot, but I can't see why it wouldn't work. It might even work better than on the stovetop. But she'll almost certainly have to halve the quantities or it won't fit in the pot. The basic recipe is based on two cups (about one pound) of peas and four cups of water. I don't like celery so I substitute a bunch of carrots and I also add chopped ham, and I add a bunch of garlic instead of onion. I've also found that adding chopped mushrooms improves the mixture.