steelhead or salmon fillet, skinned and pin bones removed
1 thinly sliced Walla Walla sweet onion
2 tablespoons unsalted butter
2 teaspoons Herbes de Provence (a dry mixture of savory, rosemary, fennel, thyme, basil, tarragon, marjoram, and lavender)
Sauté the sliced onion gently in 1 tablespoon of butter until it is very soft.
Place the fillet on acutting board with the skin-side down on top of apiece of parchment paper afew inches longer than the fillet at either end. With a very sharp knife held parallel to the board butterfly the fish to create a single piece of relatively equal thickness. Lay out the now larger fillet.
Distribute the sautéed onion evenly over the butterflied fillet and season with salt, pepper and the Herbes de Provence ground finely in the palm of your hand..
Tightly but carefully roll the fillet length-wise like a jelly roll with the parchment paper asan outside wrapper. Twist the ends tightly shut and tie with string. Chill in a refrigerator for two hours.
Take the fillet out ofthe refrigerator and gently remove the parchment paper. Trim upthe ends ofthe fillet. Cut narrow half-inch strips ofaluminum foil and place them around the roll every 1 1/2 inches, starting about 3/4 inch from the end. Use them as“twist-ties” tohold the roll togetheether. With avery sharp knife slice the roll evenly into roulades between each aluminum twist tie.
Heat the remaining butter in a skillet and fry the roulades in batches on eitherside for just a few minutes until lightly brown. To serve, remove the aluminum twist ties, put a few tablespoons of mustard sauce (recipe below) on a warm plate and place 3 roulades on topof the sauce. Sprinkle with some groundHerbes de Provence.
Mustard Sauce for Fish
4 large egg yolks
2 tablespoons cold water
10 tablespoons butter melted and cooled to just warm
3 tablespoons Dijon mustard
3/4 teaspoon dry mustard powder
In a small metal bowl held over a saucepan of simmering water,whisk the yolks and the water until the mixture is very thick, about three minutes. Don’t let the mixture get above 150 dedegrees. Remove the bowl from atop the sauce pan and gradually add the melted butter a bit at a time while whiskingthe sauce constantly. When all of the butter is incorporated, whisk in the two mustards and season with salt, pepper and some ground Herbes de Provence, if desired.