Prime Rib Experts: Low and Slow method?

That's the way I cook a standing rib roast, I imagine it works with prime rib steaks. Never tried it frozen though, the damage to the cell walls from freezing means your meat will dry out easier, so watch the temps and cook times.

When I buy a rib roast, I unwrap it from the plastic / butcher paper, and place it in the fridge in a colander for at least 3 days, 5 if I have time... turning it every few days. This allows water to evaporate and bacteria to tenderize the meat, it's called dry-aging.

When it's time to roast, I heat the oven to 250F. I trim the roast of any unsightly bits of meat, and rub it down with olive oil and kosher salt. I place the roast on a trivet in a steel / aluminum (not non-stick) cake pan (too cheap to buy a roasting rack and pan). Turning the oven down to 225F, meat thermometer goes into the meat and into the oven it goes.

Thermometer is set to alarm a few degrees below rare... when the alarm goes off, I zip the oven temp up to 450F to put a crust on the meat, like you said, 8-10 min.

After the oven starts to smoke real good, meat comes out, on goes the foil and a dish towel and it's off to rest for 30 mins or so.

Drippings in the cake pan go on the stove top to reduce almost to a paste. When it's real thick, red wine and real butter go in. Reduce again to desired consistency for a great "au jus"

Lots of work, but it really comes out good. Outside steaks are usually medium well to well done for the squeamish, inside steaks are medium to medium rare, depending on how long you let it rest, less rest == more rare inside steaks.

Serve it up with a bunch of steamed asparagus and mashed potatoes, mmmm now I'm hungry!

Recipe to consider:

Prime Rib

My opinion would be that there are a few things backwards with your plan. the 500 degree oven or searing pan is to hold in the juices. Doing at the end of the cook is a little useless. Low and slow is usually devoted to meat that is tough and one tries to breakdown the muscle tissue. I don't see that applying to a prime rib. I have seen prime rib recipes where the oven is turn way up and then completely off and the roast stays in the oven cooking off the residual heat. That might be considered a low and slow method but I've never done it that way.