1. Coat the inside of the slow cooker with cooking spray. Combine cornstarch and broth in cooker until cornstarch is dissolved; stir in peanut butter, curry paste, brown sugar, soy sauce, ginger and garlic. Add bell pepper, tofu and mushrooms and toss gently. Cook on low 4 hours.
2. Stir in coconut milk, lime juice and spinach, turn slow cooker to high; cook 15 minutes more.
3. Cook rice according to package directions, omitting fat and salt. Serve curry over rice. Garnish with lime wedges if desired.