Heat olive oil in a pan add chopped garlic, sliced onions, brown sugar, balsamic vinegar, and red wine, sauté it and add salt cracked black pepper, chopped mushrooms and Shitake mushrooms. To assemble the sandwich, cut the French bread loaf, slit it along the length and generously spread butter, add layer of curly lettuce leaves mushroom mixture, chopped bell peppers and generously sprinkle grated mozzarella cheese and season with chilli flakes.
Grill the loaf to melt the cheese. For the Caprese sandwich: Cut a bagel bread in half, spread butter and toast in a pan on both sides, add lettuce leaves, sliced tomatoes, mozzarella cheese, basil leaves, drizzle olive oil, balsamic vinegar, sprinkle mixed herbs and add chopped olives. Close with the top half of the bread. Gourmet sandwiches are ready to be served!.