Heat evoo in heavy large skillet over medium heat. Add onion and garlic. Saute until the onions begin to soften, about 2 minutes. Reduce heat to medium-low.

Add tomatoes, ½ cup parsley and crushed red pepper and stir until tomatoes are just tender, about 8 minutes. Add whitefish and cook until heated through, about 3 minutes.

Meanwhile, cook pasta in large pot of boiling salted water until tender but still firm to bite, stirring occasionally. Drain. Return to pot. Toss fish mixture with pasta.

Season with salt and pepper. Transfer pasta to bowl. Sprinkle with 2 tablespoons parsley and serve.