How to Make It
Heat a nonstick skillet over medium-high heat. Add chicken. Sauté 6 minutes, turning to brown all sides. Remove chicken from pan; keep warm.
Bring 8 cups water to a boil in a large saucepan. Add orzo; cook 8 minutes or until orzo is al dente. Drain in a colander over a bowl, reserving 1/4 cup cooking liquid.
Add reserved cooking liquid, chopped tomato, tomato paste, 1/2 teaspoon salt, and peppers to skillet; cook over medium-high heat for 2 minutes. Add chicken, pasta, and 3 cups spinach leaves, stirring until spinach wilts. Remove from heat; sprinkle with cheese.