This is a quick and simple dish, relatively speaking, with minimal prep required, which these days is about at the top of the priority list. A beurre blanc sauce, literally 'white butter', is done with whole butter, white wine, lemon juice, parsley and shallots at its most basic form, but is really easy to embellish with things like red bell pepper, capers and whatever else you feel like throwing in there. My ratio of butter to lemon juice wasn't high enough to make this a 'textbook' beurre blanc, but this slightly lighter version was still amazing.
The main trick to a beurre blanc is to not heat the butter to the point of splitting. I dimly remember that being around 137º from my culinary school days, but the basic technique to this pan sauce is to give your skillet a quick wipe after you've removed whatever meat you've cooked, then adding the shallots, and sweating them a minute or two. Deglaze with a shot of white wine, reduce this to 'au sec', or nearly dry, then add your whole butter. Alternate between on and off the heat, swirling your pan almost continuously, until the mixture emulsifies. Thin with lots of lemon juice, toss in some chopped parsley if you like, or cilantro, then plate 'er up.
The acidity of the white wine and lemon juice makes this sauce much lighter than you'd expect. As far as the fish goes, all I did was season it with a bit of Survival Spice® and sauteed it in our Tibvrtini Olio Extra Virgene di Oliva, then kept it warm on a sizzle plate.
If you want to keep playing with butter sauces after you've tried this, a beurre noisette, or browned butter sauce is absolutely amazing, but that's another day.
