I made this recipe, modified from From Curries to Kebabs, the other day. It's really good. (To make it vegan, omit the yoghurt or use soy yoghurt -- it's only a tablespoon, so it won't make a big difference.)
Cover 1/2 cup dried, unsweetened coconut and 2 Tbsp. raw cashews with 1/2 cup boiling water. Allow them to soak for 1/2 hour, and then put them in the bowl of a food processor or blender. Add 12 ounces canned, whole tomatoes, 2 fresh bird's-eye chiles, 1/2 tsp. garam masala and 1 tsp. salt. Blend until smooth. Add a handful of cilantro and run the food processor briefly.
Heat some oil in a pot over medium heat. Add 1 tsp. yellow split peas and 1/2 tsp. brown mustard seeds. As soon as the mustard seeds start to pop, add 10 curry leaves, 1/2 a small head of cabbage, sliced, 3 small sweet potatoes, diced, and 1 large zucchini, chopped. Add 1 cup water. Bring to a boil, cover and simmer until the sweet potatoes are tender. Add the paste and simmer 2 minutes more. Add 1 Tbsp. yoghurt and remove the pot from the heat.
(Use any vegetables you like/have on hand -- the recipe called for carrots, caulifower and green beans.)