French onion soup is a delicious and comforting classic soup made by slowly cooking down onions in butter and broth until they are caramelized and sweet. The rich, deeply flavorful soup is topped with toasted bread and melted cheese before serving. While homemade French onion soup is relatively simple to prepare, the process of caramelizing the onions can take over an hour. Many home cooks make a large batch of the soup and want to freeze the leftovers for quick meals later on. But can you safely freeze homemade French onion soup?
Can French onion soup be frozen?
Yes, French onion soup can be frozen successfully. The brothy base of the soup freezes quite well. However, there are a few things to keep in mind when freezing homemade French onion soup:
- Cool the soup completely before freezing. Divide into portion sizes and store in airtight containers or freezer bags.
- Thaw the soup in the refrigerator before reheating to prevent curdling.
- The onions may become slightly mushy after freezing. Add a bit more fresh onion when reheating if desired.
- Do not freeze the soup with the bread and cheese topping. Add these fresh when reheating the thawed soup.
Follow these tips and your homemade French onion soup should freeze and reheat beautifully. The rich, oniony flavor will remain intact.
What are the best containers for freezing soup?
The best containers for freezing soup include:
- Freezer bags – Lay the bags flat in your freezer to save space. Use freezer-grade plastic bags.
- Plastic containers with lids – Choose rigid plastic containers with tight fitting lids. Leave headspace to allow for expansion.
- Mason jars – Allow headspace and make sure jar rims are free of food residue for a good seal.
- Aluminum pans – Cover tightly with plastic wrap and foil to prevent freezer burn.
Avoid glass containers which could crack in the freezer. Freezer bags and plastic containers are affordable, reusable and freezer-safe choices.
How long does homemade French onion soup last in the freezer?
Properly stored, homemade French onion soup will last 3-6 months in the freezer. To maximize freshness and quality:
- Cool the soup quickly before freezing so it doesn’t spend much time at room temperature.
- Portion into airtight containers, leaving 1/2-1 inch headspace.
- Label containers with contents and date.
- Freeze immediately at 0°F or below.
- Avoid letting the soup thaw and refreeze.
If stored under optimal conditions, frozen French onion soup should retain excellent flavor and texture for 3-6 months in the freezer before quality starts to decline.
How do you thaw frozen French onion soup?
To safely thaw frozen French onion soup:
- Refrigerator thawing – Place the frozen soup in the fridge 24-48 hours before reheating. This is the best method as it thaws the soup gently and evenly.
- Cold water bath – Seal the soup in a bag then submerge in cold tap water, changing the water every 30 minutes. Takes 2-3 hours.
- Microwave – Reheat frozen soup in the microwave in short intervals, stirring between. May be uneven.
- Do not thaw soup at room temperature. This allows bacteria to grow.
For best results, thaw the soup overnight in the refrigerator. Then you can reheat gently on the stovetop while retaining the soup’s texture and flavor.
Can you reheat frozen French onion soup?
Yes, frozen French onion soup can be safely reheated after thawing. To reheat the soup properly:
- Thaw the soup completely using one of the safe methods above.
- Transfer the thawed soup to a saucepan and reheat gently over medium-low heat, stirring frequently.
- Avoid boiling the soup which can make it muddy. Just heat until hot, about 165°F.
- If needed, add extra broth or water to thin soup to desired consistency.
- Add more fresh onions if the thawed onions seem overly soft.
- Discard any soup that was thawed but not reheated within 2 hours.
Reheated gently on the stovetop, previously frozen French onion soup regains its rich flavor with a bit of added fresh onion if desired.
How do you freeze soup with vegetables?
To freeze soup with vegetables:
- Fully cook the vegetables before adding to soup.
- Roughly chop hardy vegetables like carrots, celery, potatoes.
- Blanch soft vegetables like spinach, until wilted then cool in ice bath.
- Cool soup completely before freezing.
- Portion into airtight containers leaving headspace.
- Vegetables may become softer after thawing but maintain flavor.
Freezing transforms the texture of most vegetables, but their rich flavors will carry through. Cook vegetables al dente before freezing soup.
Can you freeze soup with dairy?
Yes, you can freeze soup containing dairy like milk, cream, cheese or yogurt. But there are some best practices to follow:
- Use pasteurized dairy products only.
- Cool soup quickly before freezing.
- Freeze for up to 2-3 months for best quality.
- Thaw slowly in the refrigerator.
- Milk may curdle and separate when thawed – simply stir or blend to re-emulsify.
- Cheeses may become grainy – add fresh cheese before serving.
Freezing does lower the quality of dairy in soup to some degree. But frozen soups with dairy can be quite tasty with a bit of tweaking after thawing.
Can you freeze French onion soup with croutons?
It’s best not to freeze French onion soup with the croutons or bread topping. For best results:
- Freeze only the base broth, without any bread or cheese.
- Thaw the broth completely before reheating.
- Add fresh bread and cheese right before serving reheated soup.
- The crispy texture of croutons or toast won’t hold up to freezing.
- Cheese will become rubbery when frozen in broth.
Freezing the broth base separately allows you to add hot, crispy, melty bread and cheese for the classic French onion soup presentation after reheating.
What to do if soup separates after freezing?
Don’t worry if your frozen soup separates or looks curdled after thawing. This is a common issue and there are some easy fixes:
- Blended soups may separate – use an immersion blender or regular blender to re-emulsify.
- Starchy soups like bean or potato may be grainy – blend lightly to smooth out.
- Brothy soups can separate into solids and liquid – simply stir or whisk to combine.
- If dairy like cream or cheese has curdled, whisk vigorously or blend to reincorporate.
- Add a bit of fresh cream or milk to improve consistency after separation.
Don’t let separation stop you from freezing soup. Just be prepared to use emulsifying techniques after thawing to restore a smooth, creamy texture.
Can you freeze French onion soup without onions?
Onions are the star ingredient and provide the characteristic rich, savory flavor of French onion soup. Without onions, it won’t taste like the real thing. Some options if lacking onions:
- Freeze the broth base without onions, add fresh onions when reheating.
- Substitute frozen onion or dehydrated onion flakes when reheating.
- Caramelize onions to add when reheating previously frozen plain broth.
- Replace French onion soup recipe with a different frozen soup.
Onions don’t freeze perfectly when raw. But there are ways to add onion flavor back into onion-less frozen broth. Onions are a must for French onion soup.
Conclusion
Freezing homemade French onion soup is totally possible, as long as you follow some simple guidelines. Cool and portion the soup properly before freezing. Thaw slowly in the fridge before reheating gently on the stovetop. Hold off adding the toasted bread and cheese until after reheating so they retain their texture and flavor. With a few tweaks, frozen French onion soup can be just as delicious as the freshly made version.