Tortellini with Ham, Peas, and Tomato Cream Sauce

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.