How long do you cook a 1.4kg prime rib roast?

I can't tell you exactly how long to cook a 1.4kg prime rib roast. Here's why:

* Cooking time depends on the desired doneness. Do you want it rare, medium-rare, medium, or well-done? Each level of doneness requires a different internal temperature and therefore cooking time.

* Cooking method matters. Are you roasting it in the oven, grilling it, or using a slow cooker? Each method has its own heat profile and will affect the cooking time.

* Roast shape and thickness. A larger, thicker roast will take longer to cook than a smaller, thinner one.

* Oven temperature. A higher oven temperature will cook the roast faster than a lower temperature.

Here's what I can offer you:

1. Use a meat thermometer: The most reliable way to determine doneness is to use a meat thermometer. Here's a general guideline for internal temperatures:

* Rare: 125°F (52°C)

* Medium-rare: 130°F (54°C)

* Medium: 140°F (60°C)

* Medium-well: 150°F (66°C)

* Well-done: 160°F (71°C)

2. Start with a general cooking time estimate: For a 1.4kg prime rib roast, you can expect a cooking time of approximately 20-25 minutes per pound at 325°F (160°C). This is just a starting point, and you'll need to adjust based on your desired doneness and oven temperature.

3. Check for doneness early and often: Start checking the internal temperature about halfway through the estimated cooking time. Adjust the cooking time as needed to reach your desired doneness.

Remember: It's always better to undercook a roast than to overcook it. You can always cook it a little longer if needed, but you can't uncook it!

I hope this helps! Happy cooking!