2 tablespoons snipped fresh Italian (flat leaf) parsley
1 teaspoon lemon peel, finely shredded
Cook pasta according to package directions, omitting salt; drain. Return pasta to pan; cover and keep warm. Meanwhile, drain tuna, reserving oil. If necessary, add enough olive oil to measure 3 tablespoons total. Flake tuna; set aside.
In a medium saucepan heat the 3 tablespoons of reserved oil over medium heat. Add fennel; cook for 3 minutes, stirring occasionally. Add garlic, crushed red pepper and salt; cook and stir about 1 minute or just until garlic is golden.
Stir in tomatoes. Bring to boiling; reduce heat. Simmer, uncovered, for 5 to 6 minutes or until mixture starts to thicken. Stir in tuna; simmer, uncovered, about 1 minute more or until tuna is heated through.
Pour tuna mixture over pasta; stir gently to combine. Sprinkle each serving with parsley and lemon peel.