Peel and finely chop the onions. Wipe the pieces of peppers and cut them into cubes. Wash the tomatoes, cut them in half, deseed them and cut the flesh into cubes. Peel and chop the shallots.
In a skillet, heat 3 tablespoons of oil. Add the onions, then the diced peppers and tomatoes to sauté over high heat. Add salt and pepper. Book. Scrape, trim, wash and drain the mussels. Wash the clams and cook them for 1 to 2 minutes over high heat so that they open on their own.
In a saucepan, pour the wine and the chopped shallots. Add the mussels, cover and let them open over high heat. Drain them and strain their juice. In a skillet, sauté the scallops with a tablespoon of oil. In a deep dish, combine the sautéed vegetables, mussels, scallops and clams. Cover with aluminum foil and keep warm over a bain-marie.
Brush the steaks with olive oil, place them skin side down on a grill and grill them, 7 to 8 minutes, until the skin is crispy.
Reduce the cooking juices of the mussels for 5 minutes. Add the saffron and liquid cream while whisking. Let cook for 2 minutes. Adjust the seasoning and add the finely chopped dill.
Coat the hot serving plates with the sauce, place the salmon steaks in the center and scatter the vegetables and shellfish over them.
Serve immediately.
