1 ounce walnuts or raw, unsalted cashews (about ¼ cup; for optional garnish)
Cook the pasta according to the package instructions. Drain and rinse with cool water, return the pasta to the pot, and set aside.
Heat 1 tablespoon of water in a large frying pan over medium-high heat. When the water starts to sputter, add the mushrooms and onions, and cook while stirring for about 5 minutes, adding a little water as needed to prevent sticking. Stir in the garlic, and cook for 1 to 2 minutes more.
Stir in the diced tomatoes (with accompanying liquid) and oregano, then cover and cook for 10 minutes, stirring once or twice.
Stir the tomato sauce into the pot of pasta, along with the chopped basil. Serve as is, or topped with finely ground cashews or walnuts (using a rotary cheese grater to create a parmesan-like topping).
Optional vegetables: You may also add in other ingredients that are reminiscent of pizza, like bell peppers, zucchini, and fresh thyme. A handful of chopped fresh greens would also be good (kale, chard, spinach, collards).
I like sweet yellow onions in this recipe, but any kind may be used, even shallots and red onions. If you are a big garlic lover, you may want to add in another clove or two.
Tomatoes: Fresh tomatoes may be used as well, and would be especially good when they are in season. I use salt-free diced tomatoes, but if I can find whole peeled tomatoes that are also salt free, I will use those too.
Sauce: This dish has a light sauce, but if you want more sauce you can add in a half or full 15-oz. can of salt-free tomato sauce, or some tomato paste, with the diced tomatoes.
Serving Size:¼ recipe, 1.75 cups
Above: garnished with grated walnuts (using a rotary cheese grater).