In a medium bowl, add fennel, red onion, vinegar and salt. Mix to combine. Set aside to marinate for at least 10 minutes.
In a large bowl, add the lettuce, radicchio, cucumber, meat, and cheese.
Add all dressing ingredients to a jar with a tight fitting lid. Shake vigorously to combine.
Add fennel/red onion (leaving the liquid behind) to the large bowl. Pour ⅔ of dressing over the salad and toss to combine. Taste and add more dressing, if needed.
Serve topped with basil, peppers/olives/pepperoncinis (if using), freshly grated black pepper, and a side of crusty bread (if using).