Cook mushrooms, bell peppers and onion in oil in large nonstick saucepan until tender-crisp. Add rice; cook about 2 minutes until slightly browned.
Add 1 cup hot broth to rice mixture; cook stirring constantly, until broth is almost absorbed. Repeat, adding 1 cup broth at a time, stirring until broth is almost absorbed, about 15 minutes total. Add spinach. Cook 3 minutes more, stirring constantly, until broth is almost absorbed and rice is tender. Stir in butter, cheese and cream.