Bone marrow mac ’n’ cheese: 64 cents/serving

In a revelation I’m sure will surprise absolutely no one, I admit I was not sober when I came up with this idea.

But, then again, I’d be willing to guess the person who came up with deep-fried butter on a stick was not sober at the time either, and that one made history.

Part of the difficulty in roasting marrow bones is getting all the marrow out in a solid—not rendered—state. Obviously this process is going to result in some inaccessible pockets of the stuff tucked above and below bone crevices and along walls too narrow to reach with a utensil. It will come out if it’s rendered, sure, but what to do with it then?

Answer: Toss some with bread crumbs and salt and roast until crunchy, and use the rest to make a roux.

As we all know, there’s only one proper use for toasty bread crumbs and a savory roux: MAC ‘N’ CHEESE.

This recipe is enough for 4 very generous servings, or 6 polite-sized servings.

• Leftover beef or veal bones with some marrow still left in them; enough to produce a few tablespoons’ worth of rendered fat: $0
• 1 1/4 cup good-quality bread crumbs from leftover bread: $0
• 8 oz. pasta of your choice: 50 cents
• 3 T flour: 2 cents
• 1-2 T butter: 10 cents
• 1 T mustard powder: 5 cents
• 3 cups whole milk: 48 cents
• 1 bay leaf: 1 cent
• 2 tsp onion powder: 2 cents
• 1 egg: 12 cents
• 4 oz. grated Parmesan: $1.25
• Salt to taste: 1 cent
• Freshly ground pepper to taste (white or black): 1 cent
TOTAL: $2.57/4 = 64 cents/serving 

Roast the bones standing up in a steep-sided dish at 400 degrees, until all the fat has rendered out of the center. (Below are the bones before most of the marrow was eaten.)

Toss the bread crumbs with enough beef marrow to coat, add a pinch of salt, spread on a cookie sheet, and toast at 350 degrees until well-browned and very crunchy.

Grease an 8 x 8 Pyrex dish or casserole dish with similar capacity.

Heat a pot of salted water for the pasta.

Heat remaining marrow plus enough butter, if necessary, to equal 3 tablespoons in a medium pot over medium heat. Whisk in the flour and mustard and keep stirring for about 5 minutes; the color should be a light golden brown. Slowly add the milk, a little at a time, while still whisking constantly. There should be no lumps. When it’s all combined, add the bay leaf and onion powder and simmer on low for 10 minutes, stirring often, until thickened.

Cook the pasta just until al-dente stage; it should be too firm to consider edible, but not totally hard.

Beat the egg in a medium bowl. After the sauce has simmered, pour about 1/2 cup into the bowl with the egg, whisking all the while. When well combined, pour back into the pot with the rest of the sauce, add the cheese, and whisk to combine. Season to taste with salt and pepper.

Drain the pasta and return it to the pasta pot. Pour in the sauce, stirring well to combine. Pour the mixture into the prepared dish and bake at 350 degrees for about 30 minutes. Remove from oven and top with the bread crumbs.