You know what we need more of in this world? No, no. I mean aside from Mr. Wizard episodes and eternal puppies. We need more slow-cooked, fall-apart tender meat sandwiches. Sure, we've got barbecue—pulled pork on a bun, brisket on white bread, and the like—pastrami and corned beef make the list, as do some Mexican torta fillings, or a good beef Po' Boy, or a Chicago-style Italian beef. If you want to stretch it, maybe you can even count a Sloppy Joe among the mix. Still, it's not enough.
Up in my part of Harlem, soul food and French cuisine define the restaurant scene, which means that EVERY supermarket in a 10 block radius sells a steady stream of oxtail. Why not start our braised meat sandwiching right there?
For this sandwich, I go with a very European-style braising method: I start by giving the oxtails a good hard sear to develop browned flavors, then add a mirepoix of onions, carrots, and celery, along with a bit of tomato paste for body and color. To this mixture, I add some red wine (which I reduce in order to maximize flavor), and then some chicken stock. If you have a good home-made beef stock, that would be best, but if you're going store-bought, chicken is the way to go (store-bought beef stock has very little actual beef in it and has an off-putting, tinny flavor).
From there, it's into a low oven for some slow cooking.
Oxtails are like the Fort Knox of connective tissue. They're collagen repositories. If people were connective tissue, then China would be oxtails. (Or does that analogy go the other way around?)
This is the secret to the ultra-rich, mouth-coating texture oxtail gets after cooking. See, as it simmers away in its bath of flavorful liquid, the most important change that takes place in is that the collagen‐a tough, stretchy, rubbery tissue—slowly breaks down into gelatin. This gelatin is a protein that dissolves in water and forms a very loose matrix, giving that water thickness and texture.
The key to a successful braised meat sandwich is to make sure that you cook down the stock enough that the meat can form a tight, marmalade-like layer. Wet meat is rarely appropriate in this world, and certainly not in a sandwich. Your goal is to get that braised and shredded oxtail to the consistency of good pulled pork. Moist, but not wet.
How do we do that? I like to pick the bones out of the stock after they're fall-apart tender, then while they cool, strain that stock through a fine mesh strainer and carefully reduce it on the stovetop. As it reduces, the flavors concentrate, but more importantly, the gelatin that was extracted and created from all that connective tissue will concentrate, forming a tighter and tighter protein net, until the resulting reduced stock is almost syrupy and sticky in texture.
This is exactly what we're going for. Stirring the picked and shredded meat from the oxtails back into this reduced stock results in a sandwich filling (or toast spread or burger topping or any number of other applications) that is unrivaled in terms of sheer, juicy meatiness.
To be honest, that's the most important bits of the recipe right there. The rest is just window dressing. I pile my oxtail onto the bottom half of a split and toasted ciabatta roll, then top it off with some pickled hot cherry peppers (I love those things for their vinegary heat), and some slices of nicely aged Gruyère or Comté cheese before broiling it all and closing up the sandwiches.
Serve these suckers with some good cornichon-style pickles and a glass of full-bodied red wine to wash it down. It's a sandwich that eats like a steak.
About the author: J. Kenji Lopez-Alt is the Chief Creative Officer of Serious Eats where he likes to explore the science of home cooking in his weekly column The Food Lab. You can follow him at @thefoodlab on Twitter, or at The Food Lab on Facebook.