1. Melt butter in large skillet. When hot, add bacon. Stir with a wooden spatula and cook 3 minutes. Remove bacon to drain.
2. Add onion and cook until onion is soft, about 5 minutes. Pour on the wine and stir until the wine is evaporated. Set aside but keep warm.
3. In a deep serving dish, beat together eggs with parsley, salt, plenty of pepper and parmesan. Add reserved onion mixture. Toss with hot pasta and mix well. Add bacon and toss again.