Au Jus - A Little Spoon

Get the Recipe: Au Jus

A little extra something to go with the prime rib! ;)

4.84 from 6 ratings

Yield12 people

Prep20

Cook6

Total6 20

Sometime between when the roast goes into the fridge and the day you cook it, make the au jus. Preheat the oven to 400°F (204°C). Place the ribs you cut off of your roast, plus the rest of the au jus ingredients onto a baking sheet. Quarter a yellow onion and half a head of garlic. Coat with oil and season with salt and pepper. Toss to fully coat the bones and aromatics and then bake for 45 minutes.
Once baked, add everything into a stock pot and fill until all of the bones are covered with water or chicken stock if you really want to go big. Don't forget to deglaze your baking sheet with some water and the back of a spoon. To do this scrape and dissolve all of the nicely browned bits into the water. Pour that into the stock pot as well. Cook for 4 hours or until the marrow in the bones looks pitted and the cartilage in the oxtails becomes translucent.
Strain the liquid out, separating the juice from the fat, and save both in lidded containers until it's time to use or finish into a gravy. You should have roughly 4 cups (960ml) of stock. About 30 minutes before eating the Prime Rib, reheat your au jus and whisk in a pat of butter to give it a more creamy texture.

What do I do if I want gravy and not au jus?

If you want to make gravy, you still need to make au jus. It's what you do to the au jus afterward that is important. To make gravy, reheat or keep the finished au jus in a small pot on the stove. Next, measure out 15-16g, by weight, of both all purpose flour (2 tablespoons) and saved beef fat (1 tablespoon+1 teaspoon, from the drippings) per 240ml (1 cup) of au jus.
In a separate sauce pot, heat up beef fat until fully melted and fragrant and then add in flour. It's important to cook out any liquid that hitched a ride with the fat before adding in your flour otherwise, "Oh hey! NOODLES!" To help you, if there is any water present the oil will sputter when it gets hot and stop when the water has cooked out. With a flat wooden spatula, stir the roux for at least 15 minutes to cook out the flour flavor and turn it into a slightly toasted, blonde roux. Then, add in re-heated, au jus and whisk until everything comes to a boil. At this point you can turn down or turn-off the heat. Continue whisking until the gravy thickens enough to coat the back of a spoon.