Prosciutto Carbonara with Spinach

In a large skillet, heat oil and half of prosciutto over medium; cook, stirring occasionally, until prosciutto is crisp, 3 to 4 minutes. Drain on paper towels; crumble. In a bowl, whisk together whole eggs, yolks, and cheese.

Cook pasta in a pot of salted boiling water 1 minute less than package instructions. Reserve 1 cup pasta water, then drain. Slowly whisk 1/4 cup pasta water into egg mixture. Add pasta and spinach to skillet, then slowly add egg mixture to pasta.

Stir constantly over low heat until sauce thickens and clings evenly to pasta and spinach wilts slightly, 3 to 5 minutes; add more pasta water as needed to create a silky sauce. Stir in all prosciutto. Serve with more cheese and pepper.