Soak raisins in lukewarm water for 30 minutes. Drain and set aside. Preheat oven to 400 degrees F (200 degrees C).
Heat olive oil in a large saucepan or skillet over high heat. Saute onion and garlic until soft. Stir in raisins, tomatoes, olives, pine nuts and capers. Cover pan, reduce heat to medium and cook for 15 minutes.
Season the steaks with salt and pepper. Place in a lightly oiled baking dish and cover with the cooked sauce. Bake in preheated oven for 15 to 20 minutes, until steaks are firm.