Steaming fish in sealed parchment paper is a classic preparation. But this old-school dish always looks impressive when brought to the table, the parchment is torn open, and beneath the steam, the main attraction makes its entrance. It’s actually a really quick, easy, and even healthy preparation.
Preheat the oven to 400 degrees.
Heat the butter and olive oil in a sauté pan over medium-high heat. Add the mushrooms and sauté until browned. Season with salt and pepper, to taste. Set aside.
Clean and score the fish. Season both sides with salt and pepper, to taste. Cut four 1 ½-foot lengths of parchment paper. Fold each of them in 1/2, and then cut them so that they will make heart-shaped paper when opened to make the pockets.
For each packet, ladle 1 tablespoon of mushroom duxelles in the center, place the fish on top, ladle tomato concassé on top of the fish. Layer the ramps over the concassé. Place the morel mushrooms along the sides of the fish.
Divide the wine and lemon juice evenly over each portion of fish, and season with salt and pepper, to taste. To close the packages, brush egg whites all along the outside edges of the inside of the paper surrounding the fish. Fold the paper to match up all sides and press together.
Then, brush 1 side with egg whites, and start folding the paper over in folds about as long as the tip of your thumb to its knuckle, pressing tightly to close all along the way. (It’s important to get a good seal so that the fish steams in the packet.)
Place the packages on a cookie sheet and put in the oven until they expand fully, about 15 minutes. Place on a plate, tear open (be careful of the steam), and serve!