1 medium sweet potato, peeled and cut into 1 1/2-inch cubes
1 small onion, finely chopped
1 clove garlic, minced
1 1/2 teaspoons best-quality curry powder
1/4 teaspoon ground cumin
2 tablespoons tomato paste
3 tablespoons potato starch
1 pound firm tofu
1/2 cup brown rice, cooked -- add some mirin for flavor
2 tablespoons minced chives
3 tablespoons roughly chopped cilantro
3/4 teaspoon salt
1/8 teaspoon freshly ground pepper
4 low-fat whole-wheat buns
Olive-oil cooking spray