There are a few ways to cook prime ribs in the oven. - My favorite method is to give it a blast on high heat (220 C/ 425 F) for a few minutes then reduce heat (165 C/ 325 F) and cook until I reach the desired temperature of doneness. - My second favorite method is, of course, slow-cooking - cook it at a lower temperature (160 C/ 325 F ) for a long time until the meat is soft and tender. - Another way would be to cook it on high heat (220 C/ 425 F) for a shorter time, then turn the heat off and let the meat cook in the residue oven heat - this works great if you like medium-rare.