Buying a pre-cooked ham is one of the smartest moves a home cook can make. It takes the stress out of holiday hosting, Sunday dinners, or meal prepping for the week. However, the term “pre-cooked” can be a bit of a double-edged sword. While you don’t have to worry about the meat being raw, you do have to worry about it becoming a dry, salty brick if you leave it in the oven for too long. Knowing exactly how long to cook ham already cooked is the difference between a succulent, mouth-watering centerpiece and a kitchen disappointment.
Understanding Your Pre-Cooked Ham
Before you even preheat the oven, it is vital to understand what you are working with. Most hams sold in grocery stores are labeled as “fully cooked” or “ready to eat.” This means the meat has already been cured and heated to a safe internal temperature during processing. Your job isn’t to “cook” it in the traditional sense, but rather to reheat it thoroughly while maintaining its moisture and enhancing its flavor with glazes or aromatics.
There are three main types of pre-cooked hams you’ll likely encounter.
- The first is the spiral-sliced ham, which is incredibly popular because it is pre-cut into thin, uniform slices around the bone. This makes serving a breeze, but it also means the meat is more prone to drying out because more surface area is exposed to the heat.
- The second is the whole or half bone-in ham. These take a bit longer to heat through but generally retain more moisture.
- Finally, there is the boneless ham, which is easy to carve and heats relatively quickly.
General Timing Rules for Reheating
The most reliable rule of thumb for reheating a fully cooked ham is to aim for 10 to 15 minutes per pound. However, this varies based on the temperature of your oven and the specific cut of meat. Most experts recommend setting your oven to a low temperature, usually 325°F. This gentle heat allows the warmth to penetrate the center of the ham without scorching the exterior.
If you are reheating a bone-in ham that weighs about 10 pounds, you are looking at a total time of roughly 2 to 2.5 hours. For a smaller boneless ham, it might only take 45 minutes to an hour. The goal is to reach an internal temperature of 140°F, which is the standard for “reheated” ham according to food safety guidelines. If the ham was not fully cooked when purchased, you would need to hit 160°F, but for the sake of this guide, we are focusing on the common “ready-to-eat” variety.
How to Prepare the Ham for the Oven
Preparation is the secret to moisture. When you take the ham out of its packaging, do not just toss it onto a baking sheet. Use a roasting pan or a deep baking dish. To prevent the ham from drying out, pour about a half-cup of liquid into the bottom of the pan. This could be water, chicken stock, apple juice, or even ginger ale. The liquid creates a steamy environment that keeps the meat tender.
Covering the ham is the next non-negotiable step. Use heavy-duty aluminum foil to wrap the ham tightly or cover the entire roasting pan. This traps the steam inside. If you are using a spiral-sliced ham, consider placing it cut-side down in the pan to protect those delicate slices from the direct heat of the oven.
The Art of Glazing
While the ham is reheating, you have the perfect window to prepare a glaze. Most hams come with a packet, but a homemade glaze is always superior. A classic mix of brown sugar, Dijon mustard, and a splash of bourbon or pineapple juice creates a beautiful lacquer.
Timing the glaze is critical. If you put the glaze on at the beginning of the reheating process, the sugars will burn long before the ham is hot. Instead, wait until there are about 20 to 30 minutes left on your timer. Remove the ham from the oven, increase the temperature to 400°F or 425°F, and brush the glaze generously over the surface. Return it to the oven uncovered for those final minutes to allow the glaze to caramelize and become tacky.
Factors That Influence Cooking Time
Several variables can shift your timeline. The temperature of the ham when it enters the oven is the biggest factor. If you take the ham straight from the fridge, it will take the full 15 minutes per pound. If you let it sit on the counter for 30 to 60 minutes to take the chill off (which is recommended for even heating), you might find it reaches the target temperature a bit faster.
The shape of the ham also matters. A long, thin ham will heat more rapidly than a round, bulbous one. Additionally, the oven’s accuracy plays a role. Many home ovens fluctuate by 25 degrees or more. This is why using a meat thermometer is far more effective than relying solely on a kitchen timer. Insert the thermometer into the thickest part of the meat, making sure it does not touch the bone, as the bone conducts heat differently and can give a false reading.
Keeping the Ham Moist After Cooking
Once the ham has reached 140°F and you’ve achieved that perfect golden-brown glaze, the work isn’t quite over. Rest is essential. Let the ham sit, tented loosely with foil, for at least 15 to 20 minutes before carving. This allows the juices to redistribute throughout the meat. If you cut into it immediately, all that precious moisture you worked so hard to preserve will run out onto the cutting board, leaving you with dry slices.
If you find yourself finishing the ham earlier than expected, you can keep it warm in an oven set to the “warm” setting (usually around 170°F to 200°F) for an hour or so. Just keep it tightly covered so the moisture stays put.
Alternative Reheating Methods
While the oven is the gold standard, it isn’t the only way. If your oven is occupied by side dishes, you can use a slow cooker. This is particularly effective for smaller boneless hams or spiral slices. Add a bit of liquid, set it to low, and heat for 3 to 4 hours. The slow cooker is essentially a moisture chamber, making it almost impossible to dry out the meat.
For those in a rush, you can technically use a microwave for individual slices, but it is not recommended for a whole ham. The microwave tends to make the texture rubbery and unevenly heated. If you must use it, cover the slices with a damp paper towel and use a medium power setting.
Safety and Storage of Leftovers
Leftover ham is arguably better than the main event. It can be used in sandwiches, omelets, split pea soup, or casseroles. To store it safely, carve the remaining meat off the bone and place it in airtight containers or heavy-duty freezer bags. Leftover ham stays fresh in the refrigerator for 3 to 5 days.
If you won’t get through it all in a few days, ham freezes exceptionally well. It can be kept in the freezer for 1 to 2 months without significant loss of quality. When you’re ready to use it again, thaw it in the refrigerator overnight before reheating.
FAQs
How do I prevent a spiral ham from drying out?
The best way to prevent a spiral ham from drying out is to cook it cut-side down in a pan with a small amount of liquid, like water or juice. Ensure the pan is tightly covered with aluminum foil to trap steam, and only uncover it during the last 20 minutes if you are applying a glaze.
Can I cook a pre-cooked ham at a higher temperature to save time?
It is not recommended to reheat a pre-cooked ham at a temperature higher than 325°F for the bulk of the process. High heat will dry out the exterior and cause the edges to become tough before the center is warm. Low and slow is the secret to a juicy ham.
What internal temperature should a pre-cooked ham reach?
A fully cooked ham should be reheated to an internal temperature of 140°F. This temperature ensures the meat is hot and safe to eat without overcooking it. Always use a meat thermometer inserted into the thickest part of the ham for an accurate reading.
Do I need to wash the ham before putting it in the oven?
No, you should never wash a ham or any poultry or meat. Washing meat can spread bacteria around your kitchen surfaces. Simply remove the ham from its packaging, pat it dry if necessary with a paper towel, and proceed with your preparation.
How long can a cooked ham sit out on the table?
According to food safety guidelines, a cooked ham should not sit out at room temperature for more than two hours. If the temperature in the room is above 90°F, that window drops to one hour. After that, it should be refrigerated to prevent the growth of harmful bacteria.