Creamy Spinach Chicken Dinner

1 1/2 c. uncooked penne
1 lb chicken breasts, cubed
1/2 c. chopped onion
2 tsp olive oil
1 can cream of mushroom soup
1 c. heavy cream
10 c. coarsely chopped fresh spinach
2 c. mozzarella
1/8 tsp pepper

Cook pasta to pkg directions. Meanwhile cook chicken and onion in oil until done. Stir in soup and cream. Bring to a boil over med heat. Reduce heat, simmer, uncovered, for 2 min. Stir in spinach, cheese and pepper, cook for 1-2 min or until spinach is wilted and cheese is melted. Drain pasta and add to chicken mixture, toss to coat.