Melt butter in a large saucepan over medium-high heat. Add 3/4 cup leek, 1/2 cup fennel, and bell pepper; sauté 5 minutes or until tender. Add barley, thyme, and garlic; cook 2 minutes, stirring constantly. Stir in 2 cups broth, and cook 10 minutes or until liquid is nearly absorbed, stirring constantly. Stir in remaining 3/4 cup leek, 1/2 cup fennel, 1 1/2 cups broth, and wine; cook until liquid is nearly absorbed, stirring frequently (about 45 minutes). Stir in the cheese, parsley, and black pepper. Sprinkle with olives; garnish with fennel fronds, if desired.