1. Use a piece of dental floss (unflavored, or wash off any mint flavoring) to slice goat cheese into quarter inch thick rounds.
2. In a small bowl mix the egg white with 1/2 tsp of water and pour the panko breadcrumbs onto a separate plate.
3. Roll the goat cheese rounds in the egg white and then coat with the panko breadcrumbs; refrigerate for 10 minutes before cooking.
4. Toss the mixed greens with balsamic vinegar, olive oil, salt & pepper.
5. Heat up the butter with some olive oil in a large nonstick pan over medium high heat; once the butter is smoking, place the goat cheese medallions in the pan for 1 or 2 minutes on each side or until golden brown.
6. Place 2-3 goat cheese rounds atop each salad and serve immediately.