Kosher or sea salt
1 tin sardines packed in olive oil (about 4 ¼ oz.)
extra virgin olive oil
2-3 fat cloves of garlic, peeled, smashed, and roughly chopped
1 small or ½ large bulb fennel, fronds reserved
1/4 teaspoon red chile flakes, or more to taste
1 cup canned peeled tomatoes with their juice, gently crushed
2 ounces white (dry) vermouth
1 medium lemon, juice and zest
1/3 cup toasted bread crumbs
3/4 pounds dry linguine