A little bit of comfort goes a long way...

These end of winter days get me into a bit of a funk sometimes. Its not so bad, and I'm a northeasterner through and through, so I just come to expect it. As such, I do employ some coping strategies like dragging myself to yoga class even when I really don't want to leave the apartment, napping of course, and comfort food. This macaroni and cheese does a great job on this front with a creamy saucy base that is completed by a crunchy breadcrumb topping.
Here is the basic recipe, but its easy to change it up to add variety (the one above uses bacon and pepper jack cheese to this end).
Macaroni and Cheese:

6T butter
1 medium onion, finely chopped
6T a-p flour
1 quart whole milk
1T dijon mustard
1 bay leaf
1t thyme
2c sharp cheddar cheese, shredded
1c monterey jack cheese, shredded
s&p to taste
1lb elbow pasta
2c fresh coarse crumbs
1/2c parmesan cheese
2T olive oil

Preheat oven to 400 degrees and grease 9x13 pan.
Melt butter in a 5-6 quart pot, and add onions.
Cook onions until clear, about 5 minutes, stirring occasionally.
Meanwhile set a pot to boil for the pasta, and drain when al dente.
When onions are cooked through, stir in flour and cook for a couple of minutes.
Whisk in milk slowly, and then add mustard and bay leaf.
Bring to a simmer stirring frequently, and let simmer for about 15 minutes for flavors to develop.
Stir in cheeses and season to taste.
Stir in cooked and drained pasta; pour into baking pan.
In a small bowl mix bread crumbs with parmesan and olive oil.
Sprinkle on top, bake for about 15 minutes, until crumb topping is golden brown.