Saute the onions and garlic in the wine for 2-3 min. Boil the pasta in salted water.
In the meantime, chop the bacon finely and add it to the mixture with the onions. Saute for another 2-3 min. for the bacon to become crunchy.
In a small bowl, mix the cream, eggs, parmesan and parsley, season them with salt and pepper.
Strain the boiled tagliatelle and put them in the pan, stir well with the bacon and cook for 1 min.
Take the pan off the stove and quickly add the cream mixture, put it back on the stove and stir vigorously. Serve right away.