Cook pasta according to package directions; drain. Rinse with cold water and drain again. Stir dillweed into vinaigrette. Combine pasta and 2 tablespoons of the vinaigrette; cover and chill. Drain tuna. In a small bowl toss together tuna and 1 tablespoon of the vinaigrette; cover and chill up to 2 hours. Cook green beans until crisp-tender. Cover and chill up to 2 hours.
When ready to serve, arrange lettuce and radicchio leaves, if desired, on a plate. Arrange pasta, tuna, beans, olives, tomato slices, and egg on lettuce. Top salad with green onion and anchovy fillet, if desired. Drizzle with remaining vinaigrette. Serve with garlic toast, if desired. Makes 1 serving.