Bring a large pan of salted water to a boil.
Meanwhile, put the mushrooms and garlic in a food processor and blitz until finely chopped – you’re looking for a mince-like texture. (Alternatively, do this by hand, which will take a while, but it’s well worth it.)
Put a large frying pan on a medium-high heat, add the oil and blitzed veg, then season generously.
Stir in the paprika and ground cinnamon, and fry, stirring often, for 12-15 minutes, until the mushrooms have released all their liquid and started to turn golden.
Stir in the tomato paste, fry for a few minutes, then stir in the cream and cook for a few minutes more.
Take off the heat and tear in the spinach, which will wilt in the residual heat.
Meanwhile, cook the pasta according to the packet instructions.
Drain, reserving a mugful of the cooking water, then stir the rigatoni and grated parmesan into the mushroom pan.
Keep adding and stirring in a splash of the pasta water until you have a silky cream sauce, then season to taste and serve straight away.
