Put to boil some water for the pasta and add 1or 2 tsp salt to taste.Peel the mushrooms and slice them. Cut the bacon and slice 3 garlic cloves also. Pour the olive oil in a large enough pan or skillet and saute the garlic for 1-2 minutes on medium heat. Add the bacon and cook until golden brown. Add the mushrooms and let them release their water, cooking on lower heat for about 10 minutes.
Once the water comes to a rolling boil add the pasta and cook it according to package directions. Meantime, add the tomato puree to the pan, stir and let it cook for more 5 minutes. If necessary, add some pasta water to the sauce.Next, add the basil and let it release its flavor for another few minutes. Taste for saltiness, add the pepper and the remaining 2 garlic cloves (crushed or grated). Taste for acidity and add 1- 2 tsp sugar if desired. Give it another 2 minutes and turn off the heat. The sauce is ready and the pasta should be al dente by now.
Drain the spaghetti and put them over the sauce. Give it a good toss and serve immediately. Top with grated Parmesan and indulge!