Mushroom Spinach Parmesan Pizza Sauce

Steps

1. Prepare first: finely chop the mushrooms, finely dice the onion, mince the garlic and chop the spinach.
2. Heat half of the olive oil in a large skillet over medium-high heat. Add the mushrooms in an even layer and cook, stirring only occasionally, for 7 to 8 minutes, until their liquid evaporates and they turn deep golden.
3. Lower the heat to medium, add the remaining half of the olive oil and the onion, and cook for 4 minutes until soft.
4. Stir in the garlic, oregano and red pepper flakes and cook for 30 seconds until fragrant.
5. Add the tomato paste and cook, stirring, for 1 to 2 minutes until it darkens slightly.
6. Stir in the canned tomatoes with their juice, crushing larger pieces with the spoon. Simmer uncovered for 12 to 15 minutes, stirring often, until thick enough to hold a line when you drag the spoon through.
7. Stir in the spinach and cook for 1 minute until just wilted.
8. Take the skillet off the heat and stir in the Parmesan and black pepper. Let cool slightly, then spread over pizza dough; refrigerate leftovers for up to 4 days.