Asparagus and Béchamel in Parchment is so simple, yet so sophisticated.
This recipe can be doubled or tripled (or more). However make the aspaargus in multiple packets, each containing no more than 12 spears of asparagus.
- 12 spears medium or thick asparagus (trimmed)
- 4 slice prosciutto (cut in half lengthwise)
- 4 slice (2x4-inch) slices Swiss cheese
- 2 tablespoon unsalted butter (cut into cubes, divided)
- 1 tablespoon all-purpose flour
- ½ cup whole milk
- ¼ cup grated Parmesan (plus more for sprinkling)
- 1 pinch grated nutmeg
- fine salt and white pepper (to taste)
Place the oven rack in the center position then heat oven to 425 degrees F.
Prepare an ice bath.
Steam asparagus in a steamer set over boiling water, covered, until tender crisp, 3 to 5 minutes depending on thickness. Gently move the asparagus to ice bath to stop the cooking; drain and pat dry.
Lay a piece of parchment approximately 15x18-inches onto a rimmed baking sheet , then fold it in half along the 18-inch length. Open it up like a book, centering the right side of the folded area in the center of the baking sheet.
Place four of the halved prosciutto slices onto the parchment, centered between the fold and the right edge. Lay two slices of Swiss cheese on top of the prosciutto, followed by the asparagus spears in a bundle. Top asparagus with remaining slices of prosciutto and Swiss cheese; set aside.
Melt 1 tablespoon of the butter in a small saucepan set over medium-low heat. Once the butter begins to get foamy whisk in the flour and cook, whisking constantly until smooth, about 1 minute. Drizzle in the milk, whisking constantly, until the mixture is fully incorporated. Cook, whisking often, until the mixture is thickened and just becoming elastic, about 3 minutes. Add the Parmesan and nutmeg and cook, whisking constantly, about 1 more minute. Remove from heat and season with salt and white pepper.
Spoon the warm béchamel over the center of the asparagus bundle, then snuggle the remaining cubes of butter amongst the asparagus. Fold the parchment over the bundle, crimping and folding on three open sides to form a sealed packet. Transfer the packet on its baking sheet to the heated oven. Bake until heated through, 12 to 15 minutes depending on thickness of asparagus.
To serve transfer the sealed packet to a serving platter. Cut the packet open at the table and divide contents between diners.