In a large heavy skillet, heat 2 tablespoons Crisco oil over medium-high heat, until hot but not smoking. Sprinkle fillets with salt and pepper. Cook on one side, about 7 minutes, or until golden brown. Carefully turn each fillet; cook 5 minutes more. Remove from the pan and set aside.Add the remaining Crisco oil to the pan. Add onions, mushrooms, tomato, spinach, bacon and sunflower seeds; saute quickly over medium-high heat. Add vinegar; toss and cook just until warm. Place spinach mixture on 4 serving plates; top each with a sea bass fillet.