Homemade French onion seasoning mix

This homemade French onion seasoning mix is a handy pantry staple for adding rich, savoury onion flavour to casseroles, potato bakes and all sorts of everyday dishes. Made with just a handful of simple ingredients, it's easy to make in bulk. Store it in a screw-top jar in the cupboard with your other spices so it's always to hand whenever a recipe calls for a packet of French onion soup mix.

A packet of Knorr French onion soup mix was one of those ingredients that I used to keep in the cupboard without giving it much thought. I rarely, if ever, actually made soup with it. Instead, it was a quick and easy way to add plenty of savoury onion flavour to casseroles, potato bakes, savoury breads and many other dishes.

Unfortunately, dehydrated French onion soup has become increasingly difficult to find in UK supermarkets, so I decided it was time I made my own version.

This homemade French onion seasoning mix turned out even better than I'd hoped. Crispy fried onions and onion granules provide plenty of onion flavour, while vegetable bouillon adds a savoury depth, and a little cornflour helps to thicken sauces as they cook. There's also just a touch of sugar to balance the flavours. Best of all, you can make a large batch in minutes and store it in a screwtop jar in the cupboard, ready to use whenever you need it.

I've already put it to the test in my French onion potato bake, where it was sprinkled between layers of potatoes and onions before adding cream and cheese, and the flavour was amazing and just as I remembered! But there's no need to stop at potatoes. Try adding the seasoning mix to chicken casseroles, stews and gravies, stir a spoonful into a creamy sauce, or use it to add extra flavour to meatloaf, burgers or savoury bakes.

It's one of those simple seasoning mixes that can liven up an otherwise ordinary dish without having to reach for half a dozen different spices. And because you control exactly what goes into it, you can make a jarful and have your own French onion seasoning mix ready whenever a recipe calls for a packet of French onion soup.

Why I love this French onion seasoning

• I can cook old favourites again. French onion soup mix has become increasingly difficult to find, and there are several dishes I used to make that relied on it for their distinctive flavour. Now I have a homemade substitute that's to hand whenever I need it.
• It takes only minutes to make. There's no cooking involved. Simply combine the ingredients and transfer the mixture to a screw-top jar.
• It's a proper pantry staple. Make a batch and keep it with your other jars of herbs and spices, and you've always got an easy way to add extra flavour to an everyday meal.
• This recipe makes a generous batch. There's enough to use in several dishes, so you don't have to make a fresh batch every time a recipe calls for French onion soup mix.

Ingredients for French onion seasoning mix

**This is just an overview to explain why I used a particular ingredient. The complete list of ingredients and the exact measurements are on the printable recipe card at the end of this post.**

• Crispy fried onions. I bought these from my local supermarket, where they're sold in 500-gram packs. They're handy to keep in the cupboard for adding crunch to a green salad, sprinkling over a hamburger, or stirring into soups and stews for extra flavour. Of course, you could also use my recipe for crispy fried onions and make your own instead.
• Onion granules. Very important - don't confuse these with onion salt! Onion granules are simply dried onions that have been ground into small granules or a powder. Onion salt, on the other hand, is a mixture of dried onions and salt, and can contain considerably more salt than onions. Using onion salt would make the seasoning mix far too salty.
• Vegetable bouillon powder. When I was developing this recipe, I initially tried using a low-salt beef Oxo cube. It provided the savoury flavour I was looking for, but the caramel colouring in the Oxo made the seasoning mix much darker than I wanted. I switched to vegetable bouillon powder, which gave me the same savoury depth, without the dark brown colour. The bouillon I used also happens to be vegan, so provided your crispy fried onions are vegan too, the finished French onion seasoning mix is suitable for vegans and vegetarians.
• Cornflour. This adds a little body to the seasoning mix and helps to thicken sauces and casseroles as they cook. Depending on the amount of liquid in your recipe, you may need to add a little additional cornflour to achieve the consistency you prefer.
• Sugar. Sugar might seem like a strange ingredient to add to a savoury seasoning mix, but there's only a small amount. It helps balance the salty, savoury flavours and brings out the natural sweetness of the onions.
• Salt. I deliberately didn't include any salt in this seasoning mix, as I wanted to be able to add salt to my own taste when I use the mix in different recipes.

How to make French onion seasoning mix

This won't take long - just 2 easy steps.

Step 1: Place all the ingredients into a large mixing bowl.

Step 2: Mix well until completely combined. I started with a bowl that was too small and ended up having to transfer everything to a larger one, so save yourself the washing up and start with a large bowl!

Foodle Club top tips

Keep these simple tips in mind when making and storing your French onion seasoning mix:

• Use a large bowl. Once everything has been added to the mixing bowl, you'll be surprised at how much space the ingredients take up. Use a large enough bowl so you don't have to transfer everything as I did.
• Don't allow the mixture to get wet or damp. Once it's been mixed, transfer everything to a clean, dry screw-top jar.

How to use French onion seasoning mix

This homemade French onion seasoning mix can be used as a substitute for a packet of dehydrated French onion soup mix in recipes where the soup mix is used as a seasoning. As a starting point, use 4 to 5 tablespoons in place of one packet, adjusting the amount according to the recipe and your own taste.

You can also use this seasoning mix anywhere you want to add a rich, savoury onion flavour. Stir it into casseroles, stews, sauces and gravies, or sprinkle it between layers of potatoes and onions before adding cream for a French onion potato bake.

Bear in mind that this is a dry seasoning mix. If you are using it to replace canned or prepared French onion soup, rather than a packet of dehydrated soup mix, you will also need to add stock or another suitable liquid to compensate for the liquid that comes in the canned soup.

The cornflour in the mixture will provide some thickening, but the amount required will depend on the recipe and how much liquid you add. If necessary, add a little extra cornflour to thicken the sauce or gravy to your preferred consistency.

How to make brown onion seasoning mix

You can easily turn this French onion seasoning mix into a brown onion seasoning mix! Simply replace the vegetable bouillon powder with an equivalent amount of beef bouillon powder or finely crumbled beef stock cubes.

Beef stock gives the seasoning a deeper, meatier flavour and a darker colour, more reminiscent of the packets of brown onion soup mix I used to buy. I originally tested this recipe with a low-salt beef Oxo cube, and while I found the colour too dark for my French onion seasoning, it would be ideal for the brown onion version.

Different brands of beef bouillon and stock cubes vary in strength and salt content, so adjust the quantity if necessary.

Storage

• If you make this French onion seasoning mix with commercially packaged crispy fried onions, store it in a large screw-top jar in the pantry or cupboard alongside your other spices and seasoning mixes.
• If you use homemade crispy fried onions, follow the storage recommendations for those onions and keep the finished seasoning mix in the refrigerator.
• In both instances, shake the bottle or stir it before using to ensure the contents, which may have settled on standing, are well mixed.

FAQ

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