Sort the spinach carefully and wash it thoroughly under running water. Finely tear larger leaves as desired. Peel and finely chop the onion and garlic.
For the pasta, bring plenty of salted water to the boil in a large saucepan. Cook the tagliatelle in it until al dente.
In the meantime, heat the oil in a large saucepan. Steam the onion and garlic cubes in it while stirring until translucent. Add the prepared spinach and pine nuts and fry briefly until the spinach collapses. Pour in the cream, season with salt and pepper and reduce until creamy while stirring.
Drain the pasta and drain well. Add to the sauce, sprinkle with the freshly grated Parmesan and mix all the ingredients together well.