Boil chicken breasts in a medium pot in 8 cups of water, chicken broth concentrate, 1/3 of the onion, 1 bay leaves and 3 cloves of garlic. Bring to a boil and cook over medium-low heat 40 minutes. Once cooked, remove chicken and strain and reserve the broth for rice cooking. Cool and shred chicken; set aside.
Start preparing the rice in a large pot. Add 1 Tbsp. olive oil, 1/3 of onion & 1 chopped clove of garlic. Add the reserved 7 cups of chicken broth from cooking the chicken (add water to equal 7 cups if needed). Incorporate the rice, 1/2 tsp. of the paprika and season to taste. Once it boils reduce heat to medium-low. Cover and cook until the rice is completely cooked according to package directions.
Meanwhile, in a large skillet add remaining oil, remaining onion, chopped garlic, paprika, bay leaf, shredded chicken & tomato sauce. Simmer 20 minutes or until the liquid evaporates.
Preheat oven 350°F. In a 13 x 9 inch baking dish sprayed with cooking spray. Measure and reserve a 1/2 cup of the chicken mixture, 1/4 cup of the peas and a few of the pimiento strips.
Dish will be layered. Spread a layer of rice in baking dish, top with the chicken mixture, then half of the cheese and the peas. Top with another layer of rice and finish by decorating the center with the reserved chicken, peas, the pimiento strips. Sprinkle with remaining cheese. Cover with aluminum foil.6
Bake 15 minutes, uncover and bake until cheeses are melted. Let stand 5 minutes before serving.