Boil a large pot of salted water and cook your pasta till al dente. Reserve a cup of the water before you drain the pasta.
Meanwhile, heat a non-stick frying pan over a medium to high heat and fry your bacon until crispy- you don't need oil. When crispy (but before it starts to burn) take out of the pan and set aside, preferably on some kitchen roll to keep them crispy.
Add the garlic to the frying pan (again, you shouldn't need any oil - the mushrooms will cook in the bacon fat) stir for a minute then add the mushrooms.
Stir the mushrooms regularly for 5-8 minutes as you prepare the sauce - crack the yolks into a bowl or small jug and add the grated cheese. Season with a dash of salt, the herbs and a very generous crack of black pepper then whisk together.
When your mushrooms are almost done, pick out your crispiest slice of bacon and set aside. Chop the rest into approx 1 cm slices and add back to the pan with the mushrooms.
Drain the pasta, reserving a cup of the cooking water, and put back in the pan you cooked it in. Pour in the mushrooms and bacon and stir together.
Add a tablespoon of the pasta water to your sauce mix and stir together to loosen the sauce, then pour it over your pasta, mushrooms and bacon.
Stir everything together well - tongs work best for this. If your sauce is looking a bit too thick then add more pasta water, a small spoonful at a time until you get your desired consistency.
Finely dice your saved slice of crispy bacon.
Serve the pasta, making sure to disperse the mushrooms and bacon evenly (again, tongs are best here) and serve sprinkled with some extra parmesan plus the crispy bacon bits, plus some optional extra chopped parsley or chives.