Meanwhile, melt 2 Tbs. butter in a large sauté pan over medium heat. Add the chorizo and Italian sausage and sauté, breaking up the sausage with a wooden spoon, until the sausage is crumbled and golden brown, about 10 minutes. Add the onion, red and green bell peppers, celery, carrot, and garlic. Season with half the salt and cook, stirring occasionally, until the vegetables are soft and the onions are translucent, about 10 minutes. Add the remaining 2 Tbs. butter and stir until it melts. Stir in the chicken stock. Add the bread cubes and dates and the remaining salt, and gently stir to coat the bread cubes with the vegetable mixture.