Name: Crispy French Fried Onions
Prep time: 15 min
Cook time: 20 min
Total time: 40 min
Ingredients: 1.5 pounds onions, peeled and sliced paper-thin (Yellow or sweet onions work well.); 2 cups buttermilk (Helps the coating adhere; substitute with milk and vinegar mixture if necessary.); 2 cups all-purpose flour (For gluten-free use a 1:1 gluten-free flour blend.); 3 tablespoons Creole seasoning (Tony Chachere’s or any favorite all-purpose seasoning mix.); as needed cups peanut oil for frying (Use another high smoke point oil if allergic.)

I grew up with a can of French’s crispy fried onions in the pantry — they made casseroles sing and salads crackle. Making a copycat version from scratch gives you the same crunchy, savory bite but fresher flavor, better texture, and control over seasoning. These are thinly sliced onions soaked in buttermilk, dredged in seasoned flour, and flash-fried until golden. They’re perfect for topping green bean casserole, piling on burgers, or eating straight from the bowl.

Why you’ll love this dish

Homemade crispy French fried onions deliver bakery-fresh crunch and customizable seasoning without the preservatives in the store-bought cans. The buttermilk soak helps the flour cling and creates a tender-crisp finish, while frying at a high temperature (around 375°F) yields a quick golden color and minimal oil absorption. Make a big batch for holiday casseroles or a small bowl as a party snack — either way they’re a crowd-pleaser.

“These homemade fried onions are everything the canned ones are — only fresher. Crunchy, savory, and the Creole seasoning gives a faint spicy kick.” — a happy test-taster

If you want a make-ahead casserole idea that uses these onions, try topping Crock-Pot French Onion Chicken for dinner details: Crock-Pot French Onion Chicken.

How this recipe comes together

This recipe is straightforward: soak paper-thin onion slices in buttermilk to soften edges and help the flour stick; toss the soaked onions in seasoned all-purpose flour; shake off excess flour; then fry a few strands at a time in oil at 375°F until deeply golden and crunchy. Finish by draining on paper towels or a wire rack, cool completely, and store in an airtight container. Expect total active time of about 30–40 minutes depending on slicing and frying batches.

Gather these items

1 1/2 pounds onions, peeled and sliced paper-thin (yellow or sweet onions work well)
2 cups buttermilk (helps the coating adhere; plain milk with a splash of vinegar can substitute)
2 cups all-purpose flour
3 tablespoons Creole seasoning (Tony Chachere’s) — or use your favorite all-purpose seasoning mix
Peanut oil for frying (high smoke point). If allergic, use another high smoke point oil like canola, vegetable, or refined avocado oil

Substitutions/notes:

For gluten-free: replace flour with a 1:1 gluten-free flour blend or use a mix of rice flour and cornstarch (you’ll likely need to adjust amounts slightly).
If you don’t have buttermilk, stir 2 tablespoons lemon juice or white vinegar into 2 cups milk and let sit 5 minutes.

Step-by-step instructions

Heat the oil. Preheat a deep fryer or a heavy pot with oil to 375°F (190°C). Use a thermometer to keep temperature steady.
Season the flour. In a large bowl, whisk together the 2 cups flour and 3 tablespoons Creole seasoning.
Soak the onions. Place the paper-thin sliced onions into a separate bowl with 2 cups buttermilk. Let sit 10 minutes to soften and help the coating stick.
Dredge and shake. Drain onions briefly, then add small handfuls to the seasoned flour. Toss to coat and shake off excess flour — too much flour will clump and fry gummy.
Fry in batches. Fry a few at a time (don’t overcrowd) until golden brown and crisp — usually 1–2 minutes per batch depending on thickness. Maintain 375°F between batches.
Drain and cool. Remove with a slotted spoon to a paper towel-lined tray or a wire rack. Let cool completely — they crisp further as they cool.
Store. Once fully cool, transfer to an airtight container.

Safety tip: keep oil at the right temperature and never leave hot oil unattended. Overcrowding lowers oil temp and makes soggy results.

Best ways to enjoy it

Top green bean casserole, shepherd’s pie, or baked Mac & Cheese for an instant texture upgrade.
Sprinkle on salads for savory crunch.
Use as a crispy layer in sandwiches and burgers instead of bacon.
Serve as a party snack with a sprinkle of extra Creole seasoning and a small dip.
For a meaty pairing, these onions are brilliant atop Crockpot French Onion Meatballs — try pairing flavors here: Crockpot French Onion Meatballs.

Storage and reheating tips

Room temperature storage: Once completely cool, keep the onions in an airtight container with a paper towel to absorb any residual moisture. They’re best within 2–5 days.
Re-crisping: If they soften, spread on a baking sheet and reheat in a 325–350°F oven for 5–7 minutes until crisp again. Avoid microwaving — it makes them soggy.
Freezing: Fried onions can be frozen, but texture degrades. Flash-freeze on a tray, then transfer to a freezer bag. Re-crisp in a hot oven. For best quality, use within 1 month.
Food safety: Because these are fried and then stored dry, refrigeration isn’t necessary, but if you live in a very humid climate, short refrigeration (in an airtight container) is fine — just re-crisp before using.

Pro chef tips

Slice thin and even. A mandoline makes uniform, paper-thin slices that fry evenly.
Dry before coating. After the buttermilk soak, give the onions a quick drain so excess liquid doesn’t make the flour clump.
Temperature matters. Keep oil at 375°F — too cool and the onions absorb oil; too hot and they’ll burn before cooking through.
Fry small portions. Overcrowding drastically drops oil temperature and produces greasy, limp onions.
Use a wire rack to drain. A rack keeps them crisp on all sides; paper towels trap steam and can soften the bottoms.

For a different take on using crispy onions on a sandwich, check this slow-cooked French dip inspiration: Crockpot French Dip Sandwiches.

Creative twists

Spicy: Add 1 teaspoon cayenne or smoked paprika to the flour for heat and smoke.
Herb and garlic: Fold 1 teaspoon garlic powder and 1 teaspoon dried thyme into the flour for French onion–style flavor.
Gluten-free crunch: Use a mixture of rice flour and cornstarch or a certified gluten-free flour blend. Add a tablespoon of potato starch for extra crisp.
Sweet onion version: Use Vidalia or Walla Walla onions and reduce seasoning to highlight the natural sweetness.
Panko crunch: For an ultra-crunchy texture, toss briefly with fine panko after dredging (keep watch to avoid over-breading).

Common questions

Q: How long does it take from start to finish?
A: Plan about 30–45 minutes total. Slicing and frying in batches are the time factors; active time is roughly 20–30 minutes.

Q: Can I use a different oil?
A: Yes. Use any neutral oil with a high smoke point such as canola, vegetable, or refined avocado oil. Peanut oil gives a great flavor and high smoke point, but avoid it if anyone has nut allergies.

Q: Why did my onions turn soggy?
A: Likely reasons: overcrowding the fryer (drops oil temp), oil not hot enough at start, too-thick slices, or insufficient draining before frying. Keep batches small and temperature steady.

Q: Can I make these ahead for a holiday casserole?
A: Yes — make them a day or two ahead and store in an airtight container at room temperature (with a paper towel inside). Re-crisp in a low oven for 5 minutes before topping the casserole to refresh the crunch.

Q: Are these kid-friendly?
A: Absolutely — most kids love the crunchy texture. Reduce Creole seasoning if you prefer a milder flavor.

Conclusion

Making crispy French fried onions from scratch gives you fresher flavor and full control over seasoning and texture. If you’d like a reference recipe with similar steps and tips, see this detailed version from Served From Scratch: Copycat French’s Fried Onions From Scratch – Served From Scratch. Another useful write-up with step photos and variations is available here: Copycat French’s Fried Onions Recipe from Scratch – Restless ….

Enjoy the crunch — and the compliments.