Anne Burrell's Killer Mac & Cheese with Bacon

This was a disappointment.  I thought this couldn't get any better, bacon and macaroni and cheese, but there just wasn't enough cheese flavor.  Everyone loved the bacon, but the mac and cheese was uninspired.  Oh well.  We gave this a 5, and we cut the recipe in half, which are the amounts I'm typing in here.  This recipe was found in Anne Burrell's Cook Like A Rock Star cookbook, and the calories for a serving were 442 for 6 servings.

1 T extra virgin olive oil
3 slices bacon, cut into 1/2 inch strips
1 1/2 T butter
1/2 onion, diced
salt
1/4 c flour
2 c whole milk, plus more if needed (I added another 1/3 c in)
1/2 pound short pasta
1 c (3 oz) extra sharp cheddar cheese, grated
1 c (3 oz) Fontina cheese, grated
1/2 c (1.5 oz) Parmesan cheese, grated
1 T Dijon mustard
Dash of sriracha (Anne suggests Tabasco or other hot sauce, I used the sriracha)

Cook olive oil and bacon in a pan.  Cook until crispy, then remove bacon to a paper towel.  Add the butter and onion to the bacon fat, season with salt, and cook until onion is soft.  Add the four and cook, stirring frequently, for 4-5 minutes.  Slowly whisk in the milk, season with salt, bring to a boil then reduce to a simmer.  Cook over low heat for 8-10 minutes, until the mixture is slightly thicker than heavy cream.  Boil the pasta in salted water until al dente; drain and reserve.
Add the cheeses to the milk mixture and whisk to combine, then add the mustard and hot sauce and taste to check seasoning.  Add a little more milk if the mixture is too thick, then stir in the bacon and pasta.  Serve immediately or transfer to a baking dish and reheat in the oven at 375.