TOMATO AND CLAM SOUP - Lidia

Ingredients

• 6 tablespoons extra-virgin olive oil, plus more to finish
• 2 garlic cloves, peeled and sliced
• 2 dozen littleneck clams, washed and scrubbed
• ½ cup finely chopped onion
• Two 28-ounce cans whole San Marzano tomatoes, crushed by hand
• 1 large fresh basil sprig
• ¼ teaspoon crushed red-pepper flakes
• Kosher salt, to taste
• 2 cups day-old crustless bread cubes