Heat about 3 tablespoons oil in large skillet until hot. Add sausage, stir and cook until sausage is lightly browned. Remove sausage. (Note: Instead of fresh, use 4 dried chorizos.) Season chicken pieces with salt and pepper; then brown in same skillet. Remove chicken and set aside. Using about 2 tablespoons fat from skillet, saute onion, bell pepper, tomato and garlic over medium heat. Stir often until tender, about 5 minutes. Set vegetables aside. Preheat oven to 400 degrees. In a large saucepan, bring broth to a boil. In a 14-inch paella pan or large heavy deep casserole, combine rice, vegetable mixture, sausage and saffran. Season with salt and pepper. Stir in boiling broth. Arrange chicken over top and sprinkle with peas, but do not stir rice. Bake paella uncovered on lowest rack of oven for 15 minutes. Without stirring rice, sprinkle shrimp, mussels or clams and scallops over top of rice. (Stirring rice will make it sticky. Stir only if the recipe says to.) Bake until rice is tender and shellfish are opened (about 10 to 15 more minutes). Remove paella from oven. Cover pan with a kitchen towel and let rest 5 minutes. (The towel absorbs steam to keep the rice from being gummy.) Garnish with lemon wedges and serve from pan. Makes 6 servings. (Note: Saffron is the most expensive spice in the world. You can substitute 1/2 teaspoon dried thyme, 1/2 teaspoon dried marjoram and 1/4 teaspoon tumeric.)