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How to Keep Soup Warm in Lunch Boxes

Packing lunch boxes can be a challenge as you aim to keep food fresh and hot food hot. Here’s how to keep soup warm until lunch time when packing it.

How to Keep Soup Warm in a Lunch Box

This is a sponsored post written by me on behalf of Campbell’s Soup Company for IZEA. All opinions are 100% mine.

There’s a calendar for our activities. A calendar for my work schedule. And a calendar for dinner plans. On that same meal calendar, my kids also mark which two days each week they’ll be buying lunch. Sound a little complicated? It can be. But that’s how busy schedules are.

On the days when my kids aren’t buying lunch, I like to pack them nutritious food to nourish them through the school day. Each weekend, I make sure my pantry is packed with everything I need for quick and easy lunches for their lunch boxes — ones that will be good for them.

Campbells Homestyle Light Baked Potato Soup

Recently, Campbell’s challenged me to make a delicious lunch using their Homestyle Light soup. The variety I was sent was the new Campbell’s Homestyle Light Baked Potato with Bacon and Cheese. So I heated it up and got it ready to send with my kids for lunch.

This soup is creamy, and dotted with bits of bacon, potatoes and more. 

My kids love soup for lunch, especially when it’s a tasty variety like this (did you know that there are 29 varieties of Campbell’s Homestyle Soup to choose from?). And if I can’t make soup myself — though sometimes I do — I love sending them a good soup that’s filled with veggies and other quality ingredients and no added preservatives. It’s better.

But two things: 1) I wanted to let them personalize it at school and 2) I wanted to make sure it remained hot.

For the personalization, I packed toppings for their soups. Some of our favorites? Chopped grape tomatoes, chopped red bell peppers and the classic — crackers. I also love hot sauce, but that’s just me — they prefer their soup non-spicy.

But the trick to this? That comes in the technique for keeping it warm.

How to Keep Soup Warm Until Lunch Time in Lunch Boxes

Heating up a thermos for soup

Start by heating up the soup. You can stick it in the microwave, but I find the stove to be just right for this. I usually heat it on a burner set a medium until it’s bubbly. Though it’s too hard to eat then, it will be just right come lunchtime.

Next, heat up the thermos. I prefer metal thermoses for this, because I feel like they keep the heat better — and my kids tell me the same thing. What you want to do is to fill the thermos with hot water. It could be boiling, but very hot water is really all you need. Seal the container and let it sit while you finish heating the soup.

Fill the container. Once the soup is ready, empty the water from the thermos (and dry, if you wish) and then fill it with the bubbling hot soup. Seal the container immediately — and really well.

Pack it in the lunch box. And don’t forget a spoon!

One more thing … Love Campbells? Follow them on Twitter @Campbells or check out their website for Campbell’s new products and delicious Campbell’s recipes.


Friday 30th of October 2015

I'm glad really hot water works because I have been lazy about boiling the water first. I hadn't thought of toppings for a school lunch though. I need to add that.

Katie @ Recipe for Perfection

Thursday 29th of October 2015

Great tip! You've clearly got this down to a science. :)

Joy @ Joy Love Food

Thursday 29th of October 2015

My 7-year old son loves soup and I've been wanting to pack it in his lunch for school, but wasn't sure that it would stay warm, so thanks for the tips, I will give your technique a try!


Thursday 29th of October 2015

When I still made my son lunch this is how I'd send in all his hot food!

heather @french press

Thursday 29th of October 2015

I love your idea to add toppings for the soup along with the thermos!now I just wish my kids would take soup for lunch :)