Cut fish to 1 1/2 inch cubes. Heat oil at medium high in a large skillet. By using a well cured cast iron skillet, or a good grade of 'stick free' pan, you can reduce the oil by 1/2 in this dish. Use a quality 'thin' oil such as lite sesame for best effect. Saute veggies, garlic and onion until soft. Add fish and stir fry until they look opaque (about 5 minutes). Add salsa and heat until all the way hot.
Goes really well with hot garlic bread. For a full meal, add slices of fresh cucumber (or a cucumber salad), and a sliced up bosk pear with cinnimon sprinkled lightly atop the pear.