Step 1Pat the swordfish steaks dry with a paper towel on both sides. Season each side with a pinch each of salt and pepper and set aside.
Step 2Heat the olive oil, garlic and fennel seeds in a skillet over medium heat until the garlic softens and becomes fragrant, about 3 minutes.
Step 3Lay the swordfish steaks on top of the garlic and fennel seeds and cook until they turn white on the cooked side, 5 minutes. Turn the steaks over, laying them on top of any excess garlic and fennel seeds and cook another 5 minutes.
Step 4Add the white wine and tomatoes, cover the pan tightly and reduce the heat to a gentle simmer. Cook until the meat is easily penetrated with a skewer or paring knife (the swordfish must be well-done or it will be fibrous). Timing will vary depending on the thickness of the steaks -- thin steaks may take less than 5 minutes while very thick steaks may take as long as 15 minutes.
Step 5Remove the lid and transfer the swordfish to a heated platter. Increase the heat under the skillet to high and cook until the liquid in the pan reduces to a syrupy sauce, about 5 minutes. Pour any liquid that has collected in the platter into the sauce and stir in the basil.
Step 6Pour the sauce over the swordfish steaks and serve immediately.