How To Reheat A Sandwich So It's Not A Soggy Mess
No leftover meal might be as tricky to revive as a sandwich. When most home cooks try to revive a BLT, sub, or, better yet, a steak sandwich with caramelized onions, they usually just pop their food into the microwave and call it a day. But anyone who's done this knows it only causes the bread to turn into a limp, mushy disaster that won't be able to sustain any amount of delicious fillings. While you might believe this dooms you to a life of only eating frigid hoagies straight out of the fridge, a toaster oven should be all you need to bring some warmth back into your leftovers.
To reheat a sandwich in a toaster oven, start by turning on the appliance to approximately 350 degrees Fahrenheit or lower. Mild heat will prevent you from burning your food, so don't get impatient and use the highest setting available. Once you've turned on your toaster oven, cover your sandwich in aluminum wrap and place it inside for up to 10 minutes. This should be more than enough time for your leftovers to warm back up, so check after five minutes to see if it has reached your desired temperature.
Why sandwiches turn soggy in the microwave
Bread flours are made up of gluten and sugary starches. When exposed to the electromagnetic radiation of your microwave, the water molecules in your sub destroy these fragile particles from the inside out, creating a soggy sandwich in the process. Since the molecular integrity of your sub will be compromised by this heating process, the bread will turn as hard as stone once it dries up and cools in just a few minutes. You can mitigate these problems by covering your BLT in a damp paper towel and turning your microwave settings to low, but it won't completely stop the electromagnetic radiation from cooking a sandwich incorrectly.
A toaster oven avoids this issue altogether by applying consistent, regular heat radiation to your sandwich, warming up your food from the exterior. Different kinds of bread — and even bakery sweets, such as muffins — get back to temperature excellently under this method, but you must be wary of heat-sensitive ingredients such as iceberg lettuce leaves. If you can, remove any fillings that could wilt under heat before putting your sandwich in the toaster oven. Doing this will save the insides of your sandwich from turning into slop.
Other ways to reheat a leftover sandwich
While toaster ovens might be the best way to reheat a hoagie in the kitchen, they certainly aren't the only way. A regular kitchen oven works just as well at ensuring a sandwich warms up without destroying the internal structure of its bread starches, as it utilizes the same kind of indirect radiation heat. The stove has the added advantage of size, as you can easily fit footlong subs or large quantities of leftovers in a singular batch. The only downside to this method is the preheating time, so don't use it if you're craving a quick, reheated meal.
A hot skillet can also bring warmth back into a cold sandwich, although you'll have to exercise more caution and use lower heat to avoid burning the exterior of the bread. Since this method also requires you to flip your food at least once, only use it for structurally sturdy paninis or grilled cheeses. Otherwise, you risk all the insides of a BLT falling out into the hot pan as you turn your sandwich upside down. You can also use an air fryer to reheat a hoagie, but keep in mind that you'll have to wrap it in aluminum foil to prevent the scalding convection air from burning the bread, and keep any melted ingredients from making a mess inside the appliance.