Pasta and Tomato Sauce

2 tbs olive oil
1 tbs butter
1 onion, chopped
26-oz jar tomato pasta sauce
3 tbs water
15-oz can tomatoes, diced and un-drained
16-oz pkg spaghetti
8-oz pkg cream cheese, cubed

Bring a large pot of salted water to a boil.
Meanwhile, heat the olive oil and butter in a large skillet over medium heat. Add the onion and cook and stir until the onion is tender and just starts to brown around the edges, about 5 to 6 min.
Add the pasta sauce to the onion mixture. Add the water to the empty jar, close and shake to loosen rest of pasta sauce and add to the skillet along with the un-drained tomatoes. Bring to a simmer stirring frequently so the mixture doesn't burn on the bottom.
Meanwhile, cook the spaghetti in the large pot of boiling water according to the package directions until al dente.
A few minutes before the spaghetti is done, add the cream cheese to the pasta sauce. Cook and stir, using a wire whisk, until the cheese melts and the sauce is creamy. The cream cheese may not dissolve completely in the sauce because the sauce is acidic but that's OK. It will add the desired creamy texture and flavor.
Drain the pasta and immediately add to the skillet with the sauce.
Toss for a few minutes, then serve. Serves 4-6