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How to Make Onion Powder – Easy & Flavorful

You can’t beat the flavor of homemade onion powder.

I know, I know, you’re thinking, but onion powder is so cheap, why bother making your own?

Because homemade onion powder is superior in every way to the store-bought stuff, that’s why.

When it comes to spices, the adage of “You get what you pay for” has never been more accurate.

If it’s cheap, you’re losing out on flavor.

And who knows how long it’s been since that powder was actually an onion.

Have you ever bothered to read the ingredients for onion powder? There’s always some mysterious “anti-caking agent” on the label. You don’t need that.

There should only be one ingredient in your onion powder – onions.

Once you make onion powder for yourself, you’re never going to use that horrible crumbled chalk from the grocery store again.

Onion powder is pretty easy to make too.

The hardest part is the chopping, and that’s if you do it by hand. Even then it’s not horrible. If you own a food processor, forget it, this is beyond simple. It practically makes itself.

As always, when drying food or herbs, a food dehydrator is nice, but not necessary. In fact, for this project, I’d argue that by the time you had all the fussy trays loaded, you could have had your baking sheets loaded with chopped onion, in the oven, and be sipping a glass of wine with your feet up.

The upside to using a food dehydrator is a much more controlled drying environment. You won’t have to check on your onion as often towards the end.

Let’s do this!

Here’s everything you will need:

  • 2-4 medium-sized onions
  • A cutting board and knife
  • Baking sheets lined with parchment paper
  • Something to grind your dried onion flakes

Nice to have, but not necessary

Chop your onion

Okay, this is the hardest part, so hard it brought tears to my eyes. Get it? Chopping onions?

I’ll stop.

Peel and finely chop 2-4 medium size onions.

If you’re using a food processor, use the pulse option so you can control the size of your pieces. You want everything to be relatively the same size so that it will dry at the same rate.

Pulse your onions in a food processor for even pieces.

If you’re chopping by hand, the same applies.

Chopping by hand gives you more control over the size of the onion pieces.

I chopped half of my onions with a food processor and the other half by hand. Of the two, chopping by hand allowed me to get more even pieces. Your mileage may vary.

Onion juice

Moving on, we’re going to drain our onion; this will cut down on your overall drying time. And you’ll get the bonus of having freshly squeezed onion juice.

Yeah, I know it doesn’t sound very appealing, but it’s quite handy to have around the kitchen.

Add a tablespoon to cream-based soups, sauces, gravy, and dips or spreads. Add a splash to your potatoes before you mash them. Put it in anything where you want the flavor of onion, but not the actual onion pieces.

If you want to avoid ‘onion eyes’ use a wooden spoon to press the juice out of the onion.

Place a colander over a bowl and add the chopped onion to the colander. Press down firmly on the onion using a wooden spoon. Or, if you’re a glutton for punishment like me, just use your hands. Grab a handful of onion and give it a good firm squeeze. Once you’ve squeezed the juice out you can place the onion directly on your parchment-lined baking sheet.

If you use your hands and the onions are pretty harsh, you’ll probably end up with tears streaming down your face.

Ask me how I know.

Quick tip – painter’s tape is my favorite way to label jars. It’s easy to write on and peels off when it’s time to wash the lid and use it for something else.

You’ll have ¼ cup to ½ cup of freshly squeezed onion juice when you’ve finished. Put the juice in a clean jar, label it and put it in the fridge. Use it within two weeks.

Spread your squeezed onion out evenly on the baking sheet.

You want a nice thin layer; it’s okay if they touch a little, but avoid clumps of onion.

A thin layer of chopped onion ready to go in the oven.

Dry the onion into flakes

Next, place the baking sheet on the middle rack of your oven and turn your oven to the lowest setting it has. If your oven temperature doesn’t go below 175 degrees, use a cork from a bottle of wine to prop the oven door open.

Remember when we made our garlic powder how the house smelled super-garlicky?

Yeah, this is totally different.

After your onion has been in the oven for about 30 minutes, your house is going to smell amazing.

And it’s going to make you hungry, so you’re going to order a pizza from the only place in town that will deliver way out where you live. And when you open the door for the pizza delivery guy he’s going to say, “Mmm, something smells good in here.”

Ask me how I know.

Set a timer and ignore your onion for about an hour.

After the hour is up, give the onion pieces a little stir.

Moving forward, you’ll want to check on them more frequently. Every half hour or so, stir your onion and test a few pieces by crushing them. The onion is done when it crumbles easily; it will be a beautiful golden color.

Dried onion flakes all set to be ground into onion powder.

Remove the baking sheet and let the onion cool completely before you grind it.

Grinding the dried onion is incredibly easy; it practically falls apart.

The flakes of dried onion are beautiful too. I’m going to make another batch simply to keep in flake form. I want to sprinkle them on top of my macaroni and cheese before I bake it. And I think they would be a great addition in homemade breadcrumbs.  

What to grind with?

A mortar and pestle would work great for grinding onion flakes into powder. A small blade coffee grinder works great for grinding dried herbs as well.

If you plan on using a coffee grinder, I would highly recommend using one only for this purpose.

Otherwise, if you use it to grind coffee again, the oils from the coffee will pick up the flavor of whatever else you’ve been grinding. And quite frankly, onion coffee sounds gross.

I have an old electric burr coffee grinder that I use strictly for grinding herbs, and it works amazingly well. I ran a cup of uncooked rice through it on the finest setting to clean and absorb any leftover coffee oils, before I used it for herbs.

And speaking of rice…

Toss a few grains of uncooked rice into your onion powder. This will be our not-so-mysterious anti-caking agent.

Add uncooked rice to your onion powder to absorb any lingering moisture.

You can keep your onion powder fresh by storing it in a tiny mason jar. Alternatively, I like to save the spice jars with the shaker tops when they are empty and reuse them.

Here’s some more brilliant ways to upcycle old glass jars.

Store your onion powder in an airtight container, and it will be good for several months.

Sprinkle your delicious creation on mashed potatoes, sautéed summer squash, or rice pilaf. You’re going to be amazed by the difference in the taste.

Next thing you know, you’ll be rummaging through your spice cupboard wondering what else you can make for yourself.

Ask me how I know.

How To Make Onion Powder

How To Make Onion Powder

Active Time: 1 hour
Total Time: 1 hour
Difficulty: Easy

Once you make onion powder for yourself, you’re never going to use that horrible crumbled chalk from the grocery store again.


  • 2-4 medium sized onions


  • a cutting board and knife
  • baking sheets lined with parchment paper
  • a pestle and mortar or old coffee grinder
  • a tiny mason jar for storage


  1. Peel and finely chop your onions or use a food processor.
  2. Using a colander and a wooden spoon, squeeze out the onion juice and set aside.
  3. Spread your onion out evenly on a baking sheet lined with parchment paper.
  4. Place the baking sheet on the middle rack of your oven and turn your oven to the lowest setting it has.
  5. Check on your onions every half an hour and remove when they are dry and crumbly.
  6. Grind the dried onions in a mortar and pestle or a coffee grinder.
  7. Store the powder in a small mason jar with a few pieces of dried rice to absorb any lingering moisture.
How To Make Onion Powder - Easy & Flavorful

If dehydrating onions isn’t for you, why not consider freezing them instead? It’s easier than you think.

And even without freezing or dehydrating you can store onions for up to a year if you harvest, cure and store them correctly. Here’s how to do just that.

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Tracey Besemer

Hey there, my name is Tracey. I’m the editor-in-chief here at Rural Sprout.

Many of our readers already know me from our popular Sunday newsletters. (You are signed up for our newsletters, right?) Each Sunday, I send a friendly missive from my neck of the woods in Pennsylvania. It’s a bit like sitting on the front porch with a friend, discussing our gardens over a cup of tea.

Originally from upstate NY, I’m now an honorary Pennsylvanian, having lived here for the past 18 years.

I grew up spending weekends on my dad’s off-the-grid homestead, where I spent much of my childhood roaming the woods and getting my hands dirty.

I learned how to do things most little kids haven’t done in over a century.

Whether it was pressing apples in the fall for homemade cider, trudging through the early spring snows of upstate NY to tap trees for maple syrup, or canning everything that grew in the garden in the summer - there were always new adventures with each season.

As an adult, I continue to draw on the skills I learned as a kid. I love my Wi-Fi and knowing pizza is only a phone call away. And I’m okay with never revisiting the adventure that is using an outhouse in the middle of January.

These days, I tend to be almost a homesteader.

I take an eclectic approach to homesteading, utilizing modern convenience where I want and choosing the rustic ways of my childhood as they suit me.

I’m a firm believer in self-sufficiency, no matter where you live, and the power and pride that comes from doing something for yourself.

I’ve always had a garden, even when the only space available was the roof of my apartment building. I’ve been knitting since age seven, and I spin and dye my own wool as well. If you can ferment it, it’s probably in my pantry or on my kitchen counter. And I can’t go more than a few days without a trip into the woods looking for mushrooms, edible plants, or the sound of the wind in the trees.

You can follow my personal (crazy) homesteading adventures on Almost a Homesteader and Instagram as @aahomesteader.

Peace, love, and dirt under your nails,

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