01 -
In a large skillet, melt butter over medium heat. Add chopped onion, season lightly with salt, and cook until softened but not brown, about 6 minutes. Stir in diced prosciutto cotto, minced rosemary, thyme, and 1/4 teaspoon pepper. Cook until ham is warmed through and herbs become fragrant, about 4 minutes.
02 -
Add white wine and cook until reduced by half, about 2 minutes. Pour in heavy cream and nutmeg, bring to a gentle simmer, and cook while stirring occasionally until sauce slightly thickens, about 2 minutes. Reduce heat to low to keep warm.
03 -
Meanwhile, cook penne in a pot of well-salted boiling water until just shy of al dente, about 2 minutes less than package directions. Using a spider skimmer, transfer pasta directly to the sauce along with 1/2 cup pasta cooking water.
04 -
Increase heat to high and cook, stirring and tossing rapidly, until pasta reaches al dente texture and sauce thickens to coat noodles while just pooling around pan edges, about 2 minutes. Add more pasta water in 1/4-cup increments if needed for proper consistency.
05 -
Remove from heat, add thawed peas and grated Parmigiano-Reggiano, stirring rapidly to incorporate and warm peas through. Season with salt and pepper to taste. Serve immediately while hot.