Toast the bread: Heat a grill pan over medium high heat. Brush both sides of bread with clarified butter. Place on pan, and cook until golden, 2 to 3 minutes per side. Place a slice on each of four plates.
Spread an uneven layer of Gorgonzola over each slice of bread. Spoon about 2 teaspoons honey over the cheese. Sprinkle each with about 1/4 cup chopped walnuts. Divide radicchio evenly among the four sandwiches, leaving a border of Gorgonzola around the edge. Sprinkle with chives, and garnish each sandwich with 2 walnut halves.