Baked Macaroni and Cheese

This is my MIL's recipe, and it really is awesome! This makes a side dish, sized-dish,(say that 10 times fast) but I almost always double it to fill a 9 x 13 pan as a main dish. You can add anything you like to it like ham, cut up broccoli, cauliflower, etc.

Baked macaroni and cheese

1 - 8 oz. package of elbow macaroni (or you favorite shape, shells or wheels work nicely too)
4 T butter or margarine
3/4 cup bread crumbs
1 small onion, minced
1 T all-purpose flour
1 teas. salt
1/4 teas. dry mustard
dash pepper
1 1/2 cups milk (I use skim, but any kind is fine)
1 - 4 oz packages of shredded cheddar cheese (2 cups)

1) Cook macaroni as on the label, drain. Preheat oven to 350 F. Grease a 2-quart casserole. In a small saucepan over medium heat melt 2 T butter, add bread crumbs, toss to coat, set aside.

2) Meanwhile, in a medium saucepan over medium heat, melt remaining 2 T butter, add onion, and cook until tender about 5 minutes. Stir in flour, salt, mustard and pepper until blended. Slowly stir in milk, cook until smooth and slightly thickened. Remove from heat , stir in cheese until melted.

3) Place drained macaroni in casserole. Pour cheese mixture over macaroni. Sprinkle reserved crumb mixture over top.

4) Bake for 20 minutes or until bubbly and bread crumbs are golden.

Some notes: The crumbs on top are totally optional. I usually don't bother with them, although I have had fantastic results substituting French's fried onions (the ones you put on top of green bean casserole). When I double the recipe, I don't double the onion, because I'm not a huge onion fan, but don't leave it out, it truly is the secret ingredient. Also, about the onion, you could replace some of the butter with oil if you wanted, but don't replace it all, it is what helps the onion get really sweet. Also, cook the onion slowly so it doesn't brown, but a long time, so it gets really soft and sweet. I find that the roux (butter & flour mixture) sometimes seems not quite thick enough as written, so I frequently add an additional tablespoon or two of flour. Also, really let the milk mixture thicken over a low heat and be sure to turn off the heat when you add the cheese. If the sauce gets too hot after the cheese goes in, it will separate and you'll wind up with a stringy, greasy mess. (I've learned this from experience, and it still took several "lessons" to really learn it!) One last thing, sometimes when my husband makes it, he substitutes chili powder for the dry mustard and it gives it a nice, but subtle kick.