Summer Potager Burgers - Sutter Home Family Vineyards

Ingredients

• 1 zucchini, about 7" long
• 3 Roma tomatoes
• 1 yellow squash, about 7" long
• 1 tablespoon fresh thyme leaves
• 2 tablespoons extra virgin olive oil, (1 tablespoon for tomato/zucchini rings, 1 tablespoon for onion/garlic mixture)
• 1 large yellow onion
• 1 large garlic clove, minced
• 1 3/4 teaspoon kosher salt, (1/4 teaspoon for onions, 1.5 teaspoons for chuck.)
• 1 1/2 pounds fresh ground chuck
• 1/4 cup chopped fresh flat leaf parsley
• 1 teaspoon Dijon mustard
• 1 teaspoon freshly ground black pepper
• Vegetable oil for brushing grill rack
• 2 ounces Gruyere cheese, grated
• 1 large baguette
• Assorted red and green leaf lettuce leaves