1. Bring a pot of lightly salted water to a boil. Add spaghetti and cook 10 minutes or as per package directions. Drain, reserving 1 cup of the pasta water.
2. Meanwhile, add bacon to a large saute pan. Cook over medium heat 6 minutes or until slightly crispy. Drain on paper towels, reserving 2 tbsp of the drippings.
3. Blend milk, eggs, egg yolks and salt.
4. Heat bacon drippings over medium heat. Whisk in flour; cook 1 minute. Quickly pour in milk mixture, whisking constantly to keep eggs from scrambling. Cook 2 to 3 minutes until thickened. Remove from heat and whisk in 1/2 cup of the cheese.
5. Toss drained pasta with sauce, bacon, remaining 1/4 cup cheese and some of the reserved pasta water. Sprinkle with black pepper just before serving.