We bought a half a cow a few weeks ago. They asked us if we'd like the scraps, and (under the assumption that it would be soup bones and such) we said yes. But actually it's not soup bones, it's a lot of sinew and fat. So I'm rendering out the tallow to make candles (which is all kinds of exciting and fun!)
Tallow is solid at room temperature, but becomes liquid when heated, so to render the tallow I chop up the fat chunks, add a little water, and boil them until all the fat separates from all the other stuff. Then I strain it (to get out little chunks of sinew or meat) and let the water and fat separate and cool until the tallow solidifies (at which point I can pick it off the water in a big chunk).
This morning Wolf saw a container on the counter where I'd left some tallow to separate and cool overnight. He asked what it was, and we told him it was tallow "you know, the fat from the cow."
"Oh," he said knowingly, looking at the container and seeing a solid part and a liquid part, "the tallow and the oil."
"No," Hubby clarified, "the tallow is the oil, it's just solid at room temperature."
"Really?" Wolf asked.
"Sure," I interjected. "After all, cows are solid at room temperature!"