I finally made decent beef stock the other day using some of the suggestions in this thread.
Previously, I've tried it by throwing marrow bones in the crockpot. That works for chicken bones and broth, but not beef. It was watery and
blah.
I bought a 3-lb rack of beef back ribs, cut most of the meat off to cook separately, coated the (rather meaty) bones with about 2 Tbsp of tomato paste, and roasted them for an hour at 400F. When they were about done, I sauteed about 1/4 of a a chopped onion in the stock pot in about 1/4 cup of beef tallow that I had left over from the last time I cooked beef. I put the bones and juices into the stock pot, and added water well above the level of the bones in the pot. I brought it
just to a simmer, then turned the heat back down so that it would simmer very gently.
Four hours later, I had to cook myself a steak that I foolishly had pulled out of the freezer, and I also found some mushrooms on sale for a buck that day. I sauteed the mushrooms in butter, dumped half of the mushrooms and juice into the stock pot, cooked the steak, deglazed the pan, and put
that into the stockpot. I could have done the mushrooms earlier with the onion, but I wanted a few with my steak.
About four hours after that, it had cooked down about half-way, so I cooled it, strained it and put it in the fridge overnight. A stainless steel coffee filter is my favorite gadget for making stock and rendering fats, btw.
There was almost a cup of fat on top, so I rendered it down gently on the stove (like you would to make clarified butter). The rest of the stock is fabulous, although it could have cooked down more. It's a little watery. I'll know for next time.
The stock is fabulous, and so is the tallow! Beef tallow usually has a waxy, weird taste to me, and this stuff is almost as flavourful as the stock. Nice orangey colour from the tomato and beef.
Umami FTW!