These open-faced sandwiches with crisp asparagus, prosciutto and three layers of melted cheese are gooey and crunchy. More Tasty Sandwiches
Bring a large skillet of salted water to a boil. Add the asparagus and cook until crisp-tender, 2 minutes. Drain and transfer to a plate. Wipe out the skillet.
Add the oil and shallots to the skillet, season with salt and pepper and cook over moderate heat until softened, 4 minutes. Transfer the shallots to a plate. Add the tomatoes to the skillet, season with salt and pepper and cook over moderately high heat until lightly browned on one side, 2 minutes; transfer to the plate with the shallots.
Preheat the broiler. Arrange the bread on a baking sheet; toast in the broiler 3 inches from the heat, turning once, 2 minutes.
Spread the toasts with the tapenade and top with the shallots, fontina and mozzarella. Broil the tartines 3 inches from the heat for 1 minute, until the cheese has melted. Top the tartines with the asparagus and drape with the Gruyère. Broil the tartines for 1 minute longer, until the Gruyère has melted. Top the tartines with the tomatoes and prosciutto, drizzle with the vinegar and serve.
The Gruyère, olives and prosciutto in these Provençal sandwiches are delicious with a crisp Provençal rosé.