Fry the bacon in a large pot. Just before it gets crispy, add the garlic and onion. Saute until the onion is soft, about 5 minutes. Add the white wine and bring to a boil. Let it reduce by half.
In a medium bowl, whisk the eggs and parmesan cheese until creamy. Add a generous amount of freshly ground black pepper.
Add the cooked noodles into the pot containing the bacon. Stir in the egg mixture. Keep stirring for about a minute. Set aside.
In a separate pan, heat up olive oil/butter. Saute shrimp till almost cooked, add tomato paste, then mushrooms. Saute for about 2 minutes. Squeeze juice from the lemon over the shrimp and mushrooms. Remove from heat and serve with the spaghetti.