Please feel free to substitute any mild tasting white fish of your choice. A non-stick pan works best for sautèing the fish. To say that grapefruit is my favorite fruit would be an understatement, although I would like to test this recipe next time with yellow-fleshed grapefruit. My brother mentioned this combination might taste good on shark and I think he's on to something. Serving suggestion: pan-grilled asparagus, roasted potatoes and a glass of Eola Hills pinot gris. Yesiree! Source unknown. Note: I was planning to use fresh tarragon as indicated in the recipe but sadly the tarragon in my herb garden wilted from the last big freeze. Parsley stepped in and saved the day. Thank you fresh Italian parsley!