Roasted Tomato Basil Soup

INGREDIENTS

• 6 garlic cloves, minced
• 1/4 teaspoon crushed red pepper flakes
• 2 cups chopped yellow onions (2 onions)
• 3 pounds ripe plum tomatoes, cut in half lengthwise
• 2 tablespoons unsalted butter
• 1 quart chicken stock or water
• 1 tablespoon kosher salt
• 4 cups fresh basil leaves, packed
• 1 1/2 teaspoons freshly ground black pepper
• 1/4 cup plus 2 tablespoons good olive oil
• 1 (28-ounce) canned plum tomatoes, with their juice
• 1 teaspoon fresh thyme leaves