Sandwiches get old fast – especially on a cold morning. A thermos food jar (also called an insulated food jar) lets your child enjoy a warm lunch at school without a microwave. Here's how to use one properly, plus 12 hot lunch ideas that kids love.
Why use a thermos food jar for school lunches?
- Warm food without a microwave – most schools and kindies don't heat food, so the jar does the work.
- Leftovers become lunch – last night's pasta or fried rice is a ready-made school lunch.
- Works for cold food too – chill the jar and it keeps yoghurt, fruit or pasta salad cool on hot days.
- Less plastic – a stainless steel jar replaces squeeze pouches and single-use tubs.
How to keep food hot until lunchtime (3 steps)
- Preheat the jar. Fill it with boiling water, close the lid and leave it for about 10 minutes, then drain it.
- Heat the food until piping hot. Warm is not enough – it needs to be steaming when it goes in.
- Fill quickly and seal. Fill the jar close to the top (less air = less heat loss) and close the lid straight away.
For cold food, do the opposite: chill the empty jar in the fridge (or with iced water) before filling.
12 warm lunch ideas for the thermos food jar
- Spaghetti bolognese or mini pasta with meat sauce
- Mac and cheese
- Fried rice with peas, corn and egg
- Chicken noodle soup
- Pumpkin soup (pack a buttered roll in the bento compartment)
- Butter chicken or mild curry with rice
- Meatballs in tomato sauce
- Dumplings or wontons in broth
- Baked beans and mini sausages
- Chilli con carne (mild) with corn chips on the side
- Creamy chicken and corn risotto
- Porridge or oats for a cosy winter recess
Pair the jar with a bento lunch box
The easiest way to pack a balanced hot lunch is a food jar for the warm main and a bento box for everything else – fruit, crackers, cheese and veggie sticks. Our ThermoBox stainless steel lunch box with thermos food jar (Blue) and ThermoBox (Pink) come as a set: a 975 ml, 3-compartment stainless steel bento plus a 250 ml insulated food jar, with your child's name engraved free.
Quick tips
- Pack a spoon or fork in the bento box so it doesn't get forgotten.
- Teach younger kids to open the jar slowly, as the food can still be hot.
- Stainless steel isn't microwave safe – always heat the food separately, then transfer it.
- Add a named insulated kids water bottle so lunch and drink match.
FAQs
Can I put soup in a lunch box?
Only in a sealed food jar. Bento lunch boxes are leak-resistant for yoghurt and dips, but runny liquids like soup should always go in a screw-top insulated food jar.
Is the whole ThermoBox insulated?
No – the 250 ml food jar is insulated; the bento lunch box is stainless steel but not insulated.
Shop hot & cold kids lunch boxes → or browse all personalised kids bento boxes.