Cook chopped bacon in a large frying pan over medium heat until crispy, about 5–7 minutes, then transfer to a paper towel-lined plate.

In a large pot, bring salted water to a boil, add pasta, and cook according to package instructions, about 8–10 minutes, then drain and reserve a cup of pasta water.

In the frying pan, add ground beef and cook over medium heat, breaking apart and seasoning until browned, about 6–8 minutes.

Sprinkle flour over the browned beef and stir for 1–2 minutes to create a roux, ensuring the flour doesn’t taste raw.

Gradually whisk in milk and stir continuously until the sauce thickens, about 2–3 minutes, then add ketchup and Worcestershire sauce.

Lower heat, add drained pasta, and stir to combine, cooking for about 2–3 minutes.

Add most of the cheese to the mixture, stirring until melted and creamy, then top with remaining cheese and crispy bacon.

Serve in bowls and enjoy while warm, optionally garnished with fresh herbs or extra cheese.