Cook the pasta: Bring a pan of salted water to boil. Add 150g of spaghetti and cook for 8 minutes.
Prepare garlic and vegetables: Give the garlic cloves a smack, peel off the skin, and add them to the pasta water. Add 200g of cavolo nero on top of the pasta for the last 5 minutes of cooking.
Blend the sauce: Drain the pasta and vegetables, reserving some cooking water. Blend the cavolo nero, garlic, a pinch of salt, pepper, 1.5 tablespoons of olive oil, 30g of grated Parmesan, and a little cooking water until smooth.
Combine pasta and sauce: Return the drained pasta to the pan. Mix in the green sauce until the pasta is well coated.
Serve: Plate the pasta, adding dollops of fresh ricotta, a sprinkle of Parmesan, and season to taste.