Set a medium pot of water to boil. Add pasta and cook according to package directions. Drain pasta, reserving 1/4 cup cooking liquid.
Set a large nonstick skillet to medium-high heat. Add bacon and cook ‘til crisp, about 5 minutes. Remove bacon to a paper towel lined plate, reserving drippings. Add garlic to drippings and sauté 1 minute. Whisk in flour; cook 30 seconds, stirring constantly. Gradually whisk in milk, stirring constantly until bubbly and thickened, 3-4 minutes. Reduce heat to low. Add grated Parmesan, stirring until melted. Whisk in salt and reserved 1/4 cup cooking liquid.
Add hot pasta to skillet and toss to combine. Serve and sprinkle with bacon, parsley and black pepper.