Roast and skin the peppers, remove seeds, dry thoroughly, then cut into 1/4-inch squares.
In a saute pan over medium heat, cook the butter with the diced prosciutto for a minute or less, stirring frequently.
Add the peas and cook 1 minute, stirring to coat them well.
Add the pepper squares and stir for about 30 seconds.
Add the cream, salt, and several grindings of pepper. Raise heat to high and cook, stirring constantly, until the cream thickens.
Toss with hot drained pasta, swirling in the grated Parmigiano-Reggiano. Serve immediately with additional cheese.