- Cook macaroni according to package directions. Drain.
- Melt butter over medium heat in heavy saucepan. Add garlic with onion and cook until soft. Add flour and cook 1 minute. Whisk in milk.
- Cook over medium heat, stirring frequently until thickened.
- Stir in cheese, tomatoes, mushrooms, salt and pepper. Add macaroni and stir to combine. Spoon into serving bowl and top with bacon.