Crispy Sourdough Onion Rings

Name: Crispy Sourdough Onion Rings
Prep time: 15 min
Cook time: 15 min
Total time: 30 min
Yield: 6
Cuisine: American
Ingredients: 1 cup sourdough starter discard; 3/4 cup all purpose flour, divided; 1/4 cup seltzer water; 1 teaspoon sea salt; 1/4 teaspoon black pepper; 1 teaspoon garlic powder; 1 large yellow onion, sliced into 1/2 inch rings; 2 cups panko breadcrumbs; 6 cups vegetable oil for frying; 1/2 cup mayonnaise; 2 tablespoons ketchup; 1/2 teaspoon smoked paprika; 1/2 teaspoon Cajun seasoning; 1/2 teaspoon Worcestershire sauce; Salt to taste

These golden, crispy onion rings use sourdough discard for a perfect light and crunchy coating that tastes just like the restaurant version.

By Recipes By Nani· 🌍 American· July 20, 2026

recipesbynani.com

Prep

15 minutes

Cook

15 minutes

Total

30 minutes

Serves

There is something truly special about a good onion ring, especially when you have some sourdough discard waiting in the fridge. Using the discard in the batter helps create a beautiful, light texture that clings perfectly to the onions, while the panko crumbs give them that satisfying crunch we all love.

These are a family favorite at my house and make the perfect side dish for burgers or a weekend snack with friends. I always recommend letting the breaded rings rest for a few minutes before frying, as this simple trick helps the coating stick to the onion so it stays put in the hot oil.

🧺 Ingredients

1 cup sourdough starter discard
3/4 cup all purpose flour, divided
1/4 cup seltzer water
1 teaspoon sea salt
1/4 teaspoon black pepper
1 teaspoon garlic powder
1 large yellow onion, sliced into 1/2 inch rings
2 cups panko breadcrumbs
6 cups vegetable oil for frying
1/2 cup mayonnaise
2 tablespoons ketchup
1/2 teaspoon smoked paprika
1/2 teaspoon Cajun seasoning
1/2 teaspoon Worcestershire sauce
Salt to taste

👩‍🍳Instructions

1
Slice the onion into half inch thick rounds and separate them into individual rings.
2
Set up three shallow bowls. In the first, whisk together 1/2 cup flour, garlic powder, salt, and pepper. In the second, whisk the sourdough discard with the seltzer water. Put the panko breadcrumbs in the third bowl.
3
Take an onion ring and toss it in the flour mixture to coat evenly.
4
Dip the floured onion ring into the sourdough discard batter, letting the excess drip off.
5
Place the ring into the panko breadcrumbs and gently press the crumbs onto the surface so they stick well.
6
Set the breaded rings on a baking sheet lined with parchment paper and let them sit for a few minutes while you heat the oil.
7
Heat the vegetable oil in a large pot or Dutch oven to 350 degrees Fahrenheit.
8
Fry the rings in small batches for about 2 to 3 minutes, flipping once, until they are golden brown.
9
Remove the rings with a spider strainer or slotted spoon and drain them on paper towels.
10
Whisk all the sauce ingredients together in a small bowl and serve immediately with your hot onion rings.

💡 Tips

Store any leftovers in an airtight container in the fridge for up to 3 days. To get that fresh crunch back, reheat them in a 375 degree oven or air fryer for 5 to 10 minutes.

#Appetizer #Snacks #Vegetarian #Sourdough Discard

Made this recipe? Let us know how it went.