⅓ lb. prosciutto di Parma
1 lb. spaghetti alla chitarra or bucatini
4 tbsp. olive oil
4 cloves garlic, chopped
¾ to 1 lb. escarole (1 large head), shredded, or Swiss chard (1 large bunch), center stalks removed and leaves shredded
A little freshly grated nutmeg (about 1/8 tsp.)
½ cup chicken stock
1 tsp. lemon zest, plus juice of 1 lemon (about 1/4 cup)
4 large egg yolks
1 cup grated Parmigiano-Reggiano
Preheat the oven to 375°. Arrange the prosciutto on a baking sheet lined with parchment paper. Bake until crispy, 8 to 12 minutes. Let cool, then break into pieces that are a little larger than bite-size.
Bring a large pot of water to a boil for the pasta. Salt the water and add the pasta. Cook until about 2 minutes shy of the package directions. Reserve about 1 cup of the cooking water, then drain.
In a large skillet, heat the oil, four turns of the pan, over medium to medium-high. Add the garlic and swirl or stir until fragrant, about a minute. Wilt in the greens; season with salt, pepper, and nutmeg. Add the stock and lemon zest and juice. Reduce heat to a simmer.
In a bowl, whisk up the egg yolks and cheese. Gradually whisk in the hot pasta cooking water to gradually cook the yolks without scrambling them. Toss the pasta vigorously with the greens and the egg sauce until the sauce thickens and absorbs into the pasta, about 1 minute; season. Serve in shallow bowls and top with the broken crispy prosciutto.