• 1 small onion, sliced thin
• 1/4 cup olive oil
• 2 medium zucchini, halved lengthwise and cut crosswise into 1/4-inch-thick slices
• 2 garlic cloves, minced
• 6 plum tomatoes, peeled, seeded, and cut into 1/4-inch dice
• 1 teaspoon fresh thyme leaves, chopped
• 1/4 cup dry white wine
• 1 loaf Italian or French bread about 3 1/2 inches in diameter, cut diagonally into
• 1/2-inch-thick slices (about 20)
• 10 thin slices provolone cheese (about 1/4 pound), halved

Preheat oven to 450°F..

In a large heavy skillet cook onion in oil over moderate heat, stirring occasionally, until soft. Add zucchini and garlic and cook, stirring, until zucchini is barely tender. Add tomatoes and thyme and cook, stirring occasionally, about 2 minutes. Add wine and salt and pepper to taste and simmer until liquid is reduced by about half, about 4 minutes. Remove skillet from heat and cool mixture.

On a baking sheet toast bread in middle of oven until pale golden, about 4 minutes.

Mound about 2 tablespoons zucchini mixture on each toast and top with a half slice provolone. Bake crostini in middle of oven until cheese is melted and golden.