Macaroni and Four Cheeses

3 cups whole milk
4 tablespoons unsalted butter
1 medium onion, finely diced
1 bay leaf
? cup all purpose flour
salt and pepper to taste
pinch of nutmeg
? teaspoon Tabasco sauce
5 ounces Gruyere, coarsely grated (about 1 ? cups)
8 ounces blue cheese, crumbled (about 2 cups)
1 pound penned rigate pasta
1 tablespoon finely grated lemon zest
11 ounces Monterey Jack in ? inch dice
? cup chopped flat-leaf parsley
2 tablespoons fresh thyme leaves
2 ? ounces parmesan cheeses, grated (scant 1 cup)
2/3 cup breadcrumbs

Heat oven to 350. Put a large pot of salted water on to boil.
Heat milk in small sauce pan to just below simmer, stirring often. Remove from heat and cover to keep hot.
Melt butter in a medium saucepan over medium-low heat. Add onions and bay leaf
And cook, stirring occasionally, until the onion starts to soften and becomes translucent, about five minutes.
Add the flour and cook, stirring, about two minutes. Gradually whisk in hot milk. Bring to a simmer and cook 10 minutes, whisking frequently, until thickened and smooth. Season white sauce with salt, pepper, nutmeg, and the Tabasco. Discard bay leaf. Stir in Gruyere and blue cheese.
Cook the past to al dent. Drain well and return to pot. Toss the lemon zest and half the Monterey Jack into the pasta while it is stil hot. Add the cheese sauce and quickly toss to combine. Stir in the parsley and thyme and transfer half of the pasta to a 3-quart shallow casserole or lasagna pan. Sprinkle with remaining Monterey Jack and half the parmesan and top with remaining pasta. Sprinkle with the remaining parmesan and breadcrumbs.
Bake until bubbling and golden, about 50-60 minutes. Let stand about 10 minutes before serving.

This is rich and is best served with a strong flavored salad (such as arugula) with a sharp vinaigrette to neutralize the creamy entr?e.