1, To prepre croutons, preheat oven to 375 degrees. Sporead bread cubes on a large rimmed baking sheet. Bake until toasted, about 10 minutes. In a large bowl, combine olive oil, vinegar, salt & pepper. Set aside.
2. To prepare soup, heat olive oil in a large pan over medium-high. Add onion, carrot, celery and garlic. Saute 10 minutes. Add tomates and red peppers and crush with a fork. Add orange rind and juice, sugar, chile flakes, wine, chicken stock, thyme, salt and pepper. Bring to a boil. Reduce heat to low and simmer, covered, 30 minutes. Uncover and simmer over medium heat until sauce thickens, about 10 minutes. Add scallops and shrimp and cook 3 to 5 minutes. Remove from heat and stir in chopped basil.
3. Just before serving, pour oil mixture over croutons and toss well. Divide croutons among 10 serving bowls. Top with stew.