Combine vinegar, salt, pepper, honey, and mustard. Whisk oil into mixture in a continuous stream until fully emulsified.
Divide the cheese into four equal parts. Heat a large skillet or flattop grill. Add cheese in to dry, hot pan, spreading it into a square shape. Allow cheese to brown and bubble until it looks firm enough to flip. Cook on other side long enough to slightly brown. Using a metal spatula, carefully place cheese on a round or cylindrical metal mold, wrapping it around and sealing at the edge. Stand up allow to cool. Repeat for other three cheese portions.
Toss spring mix and tomatoes with vinaigrette; arrange on four plates. Top each with a frico tower; fill with portion of the salad and serve.