Melt the butter in a sauté pan & add a splash of olive oil to the melted butter…swirl together over medium heat, then add the mushrooms. Sauté the mushrooms until well caramelized. Lower the heat to low, add the sea salt & leaves from about 4 sprigs of thyme. Toss together well & set aside.
Gently tease & separate the individual radicchio leaves from the lettuce head. Rinse & dry, then place each radicchio leaf on a plate. Slice the goat cheese into ½-inch slices. Place each goat cheese slice on the individual radicchio leaves & grind the peppercorns over the cheese.
Spoon the sautéed mushrooms & thyme equally among the plates.
Drizzle balsamic vinegar over the goat cheese & mushrooms. Garnish with additional thyme sprigs, if desired. Serve & enjoy!