A perfectly cooked ham is the centerpiece of many celebrations, from Easter brunches to Christmas dinners. However, most hams sold in grocery stores are actually “city hams,” which means they are already fully cooked and smoked. When you “cook” a ham at home, you are essentially performing a delicate reheating act. The challenge lies in warming it through to the center without turning the outer edges into salty, dry leather. Mastering the oven method ensures that every slice remains as succulent as the day it was cured.
Choosing Your Ham and Understanding the Basics
Before you even preheat your oven, you need to know what kind of ham you are working with. The reheating strategy for a spiral-sliced ham differs slightly from a whole, uncut ham.
Spiral-Sliced vs. Whole Hams
Spiral-sliced hams are convenient because they are pre-cut into thin, uniform slices right down to the bone. This makes serving a breeze, but it also makes the meat more susceptible to drying out because the heat can penetrate between the slices. Whole or “half” hams that haven’t been sliced are more resilient and hold onto their moisture more effectively during the warming process.
Bone-In vs. Boneless
Bone-in hams generally offer better flavor and more moisture. The bone acts as a conductor, helping the heat distribute more evenly from the inside out. Boneless hams are easier to carve and heat slightly faster, but they can occasionally have a more processed texture. Regardless of which you choose, the oven remains the gold standard for reheating.
Preparation Steps for a Moist Result
Preparation is where the magic happens. If you simply toss a cold ham onto a baking sheet and slide it into the oven, you are likely to end up with a disappointing result.
Bringing the Ham to Room Temperature
One of the most overlooked steps in how to warm up ham in the oven is the “chill-off” period. Taking the ham out of the refrigerator about 30 to 60 minutes before heating allows the internal temperature to rise slightly. This prevents the outside from overcooking while the inside is still shivering.
Adding Liquid for Steam
Humidity is your best friend when reheating meat. By adding a small amount of liquid to the bottom of your roasting pan—water, apple juice, cider, or even white wine—you create a steamy environment. This moisture circulates around the ham, preventing the dry oven air from wicking away the meat’s natural juices.
Setting the Correct Temperature and Timing
Low and slow is the mantra for reheating ham. High temperatures will cause the proteins to contract and squeeze out moisture, leading to a tough texture.
The Ideal Oven Temperature
Set your oven to 325°F. This temperature is high enough to warm the meat efficiently but low enough to protect the delicate fats and sugars in the ham. Some experts suggest even going as low as 275°F if you have plenty of time, but 325°F is the standard for balancing quality and speed.
Calculating Reheating Time
The general rule of thumb for a fully cooked ham is to heat it for 10 to 14 minutes per pound. For a standard 8-pound ham, this means roughly 1.5 to 2 hours in the oven. If you are heating a spiral ham, aim for the lower end of that spectrum (about 10 minutes per pound) to avoid drying out those pre-cut slices.
The Importance of a Tight Seal
Perhaps the most critical step in the process is how you wrap the ham. Without a proper barrier, the heat will evaporate the moisture from the surface of the meat.
Using Heavy-Duty Aluminum Foil
Wrap the ham tightly in heavy-duty aluminum foil. If your ham is too large to wrap entirely, place it cut-side down in a roasting pan and cover the entire pan tightly with foil. The goal is to create a vacuum-like seal that traps the steam inside. If you are using a roasting pan with a very tight-fitting lid, that can also work, though foil often provides a more reliable seal against moisture loss.
The Glazing Phase: Adding Flavor and Shine
Most people want their ham to have that signature sticky, sweet crust. However, the timing of the glaze is vital. Because glazes are typically high in sugar, applying them too early will cause them to burn long before the ham is warm in the middle.
When to Apply Glaze
Wait until the last 15 to 20 minutes of the reheating process. At this point, remove the ham from the oven and increase the temperature to 400°F or 425°F. Carefully unpack the foil and brush your glaze over the entire surface. Return the ham to the oven uncovered.
Achieving the Perfect Crust
Keep a close eye on the ham during this final blast of heat. The sugars in the glaze will bubble and caramelize, creating a beautiful mahogany finish. Once the glaze is tacky and browned, remove the ham immediately.
Testing for Doneness
Because the ham is already cooked, you aren’t looking for a “safe” temperature in the same way you would for raw pork. Instead, you are looking for an “enjoyable” temperature.
Using a Meat Thermometer
The USDA recommends reheating fully cooked ham to an internal temperature of 140°F. Insert a meat thermometer into the thickest part of the ham, making sure not to touch the bone, as the bone will give an inaccurately high reading. For a spiral ham, 135°F is often sufficient, as the internal temperature will continue to rise slightly during the resting period.
The Resting Period
Do not slice into the ham the moment it comes out of the oven. Like any large roast, ham needs time to rest. During this 15 to 20-minute window, the juices that have been pushed to the center of the meat will redistribute back toward the edges. If you cut it too soon, those juices will run out onto your cutting board, leaving the meat dry.
Summary of the Oven Warming Process
To recap the most effective method:
- Remove ham from the fridge 45 minutes prior to heating.
- Preheat the oven to 325°F.
- Place ham cut-side down in a pan with half a cup of water or juice.
- Wrap the ham or the pan tightly with foil.
- Heat for 10 to 14 minutes per pound until the center reaches 140°F.
- Glaze during the last 20 minutes at a higher heat if desired.
- Rest for 15 minutes before carving.
Frequently Asked Questions
How do I prevent my spiral ham from getting dry?
The best way to protect a spiral ham is to place it face-down in the pan so the slices aren’t exposed directly to the air. Additionally, wrapping it exceptionally tight in foil and adding a splash of liquid to the pan will create a steam-locked environment that keeps the pre-cut sections moist.
Can I reheat a ham that has already been sliced?
Yes, but you must be very careful. Slices should be stacked together to mimic the shape of the original ham and wrapped in foil with a little bit of broth or butter. Heat them at 325°F for only 5 to 10 minutes, just until they are warm to the touch.
What should I do if my ham is labeled “Cook Before Eating”?
If your ham is not labeled “Fully Cooked” or “Ready to Eat,” it is a fresh or partially cooked ham. In this case, you must cook it to a higher internal temperature of 145°F and allow it to rest for at least three minutes. The reheating times for these hams are significantly longer than for city hams.
Is it better to reheat ham in a slow cooker or the oven?
While a slow cooker is great for keeping ham warm during a party, the oven is superior for the initial reheating of a large ham. The oven allows for better temperature control and provides the ability to caramelize a glaze, which a slow cooker cannot do effectively.
How long can leftover ham stay in the refrigerator before reheating?
A whole, fully cooked ham can stay in the fridge for about 7 days. However, once you have reheated it and sliced it, the leftovers should be consumed within 3 to 5 days. For longer storage, ham freezes exceptionally well when wrapped in airtight packaging.