How to Make It
In a large stainless-steel frying pan, melt the butter over moderately low heat. Add the onion; cook, stirring occasionally, until starting to soften, about 3 minutes. Stir in the tomatoes with their juice, the salt, and the pepper. Simmer for 10 minutes. Add the cream and cook for 1 minute longer.
Meanwhile, in a large pot of boiling, salted water, cook the tortellini until just done, about 4 minutes for fresh, 12 minutes for frozen. Drain the pasta and add it to the pan with the sauce. Stir in the ham and peas and cook until warmed through, about 2 minutes.
Substitute 1/4 pound sliced prosciutto, cut into thin strips, for the ham.
Stir in 1/4 cup fresh basil leaves, cut into thin strips, with the ham and peas.