These crispy onions are ultra crunchy, easy to make and so yummy! Perfect in sandwiches, burgers and salads.
Once you master these crispy fried onions, you’ll rarely buy pre-made ones again. They’re addictively crunchy, quick to prepare and versatile — great on sandwiches, burgers, salads or served as a snack with a dip.
Buttermilk Fried Onions
Soaking the sliced onions in buttermilk is a key step. Buttermilk has the right thickness to cling to the onion strands and helps the flour adhere, which builds a light, crispy crust when fried.
What type of onion to use?
A large white onion is ideal. Sweet varieties like Vidalia or cannonball onions also work well — just choose a firm, fresh onion for the best texture.
How to slice onion for fried onions?
You can slice into rings or into thin strips for onion strings. The important part is to slice very thinly — thinner than typical onion rings — and separate the strands fully so they don’t clump during dredging and frying.
How long to soak in buttermilk?
Soak for 30–60 minutes if you have the time. If you’re short on time, even a brief soak while you prepare the flour and oil will help.
Process shots: peel onion (photo 1), slice into thin strips (photo 2), separate strips (photo 3), soak in buttermilk (photo 4).
Crispy Fried Onions
After soaking, dredge the onions in seasoned flour. I season the flour with paprika, salt and white pepper, and add a little baking powder to encourage a light, bubbly crust as they fry.
Avoid tossing all the onions in the flour at once — that can cause clumping. Work in small batches, shake off excess buttermilk before adding to the flour, and coat evenly. This gives a lighter, crisper coating.
Deep Fried Onions
These are best when deep fried, much like classic onion rings. Fry in batches so the oil temperature stays consistent and the onions cook evenly. Use tongs to separate strands immediately if they stick together.
Process shots: add seasoning to flour (photo 1), whisk to combine (photo 2), add onions (photo 3), coat (photo 4), deep fry (photo 5).
Serving Crispy Onions
When the onions are deep golden and visibly crisp, drain them on paper towels and season with a light sprinkle of salt. The salt not only adds flavor but helps draw out any last bit of moisture from the batter, keeping them crisp.
How to store crispy onions?
They’re best fresh, but you can cool them completely and store in an airtight container or zip-lock bag.
How long do crispy onions last?
Stored properly, they’ll typically stay crisp for up to a week, though check after 4–5 days — they may soften over time.
What can I use crispy onions for?
These onions are perfect for sandwiches (they’re shown here on a grilled chicken sandwich), burgers, salads, soups and casseroles. They’re also great served as a finger-food appetizer with a dip like chipotle mayo.
Now for the full recipe so you can make these at home.
How to make Crispy Fried Onions (Full Recipe & Video)
Crispy Fried Onions
Equipment
- Sharp knife & chopping board
- Medium mixing bowl
- Large shallow dish
- Pot suitable for deep frying
- Slotted spoon & tongs
- Tray & paper towels
- Kitchen thermometer
Ingredients
- 1 large white onion, peeled & very thinly sliced
- 2 cups / 500 ml buttermilk, or enough to cover the onions
- 1 1/2 cups / 225 g plain / all-purpose flour
- 1 1/2 tsp paprika
- 1 1/2 tsp baking powder
- 3/4 tsp salt (plus more to serve)
- 1/4 tsp white pepper
- 4 cups / 1 litre vegetable oil, or as needed for frying
Instructions
- Combine the sliced onions and enough buttermilk in a medium bowl to cover them. Leave to soak for 30–60 minutes. If short on time, soak while you prepare the other steps.
- In a large shallow dish, mix the flour, paprika, baking powder, salt and white pepper. Using tongs, lift a small batch of onions from the buttermilk and shake off excess. Add to the flour and toss or use your hands to coat evenly. Shake off excess flour and place on a tray. Repeat with remaining onions in batches.
- Heat oil in a pot or deep pan to 180°C / 350°F. Carefully lower a batch of coated onions into the oil and immediately separate any strands with tongs. Fry until deep golden and crisp, about 2–5 minutes depending on thickness and batch size. Remove with a slotted spoon and drain on paper towels. Maintain oil temperature between batches; three batches usually works well without overcrowding.
- Sprinkle with a little extra salt to finish, then serve hot on sandwiches, burgers, salads or with your favorite dip.
Quick Demo
Notes
b) Onion slices – Slice very thinly for the crispiest result. Use a mandoline or a sharp knife and be sure to separate the strands before soaking to avoid clumping.
c) Storage – Best fresh but keep in an airtight container or zip-lock bag for up to a week; check for softening after a few days.
d) Serving – Excellent in a grilled chicken sandwich, with chipotle mayo, on burgers, salads or casseroles.
e) Calories – Approximate per serving based on the recipe: 276 kcal.
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