First up, let’s whip up that Bloomin' Sauce. Combine the tomato ketchup, prepared horseradish, mayonnaise, smoked paprika, minced garlic, kosher salt, black pepper, sour cream, cayenne pepper, and fresh lemon juice in a bowl.

Mix well until smooth. Taste and adjust seasoning if necessary. Set aside in the refrigerator to chill.

Take your sweet onion and peel away the outer layer. Slice it into rings, then separate these rings into “petals.” You should have various sizes, which adds character to your dish.

In a large bowl, whisk together the all-purpose flour, seasoned salt, black pepper, smoked paprika, garlic powder, onion powder, and cayenne pepper. This seasoned flour will give your onion petals an added kick.

In a separate bowl, mix the buttermilk, hot sauce, and egg. Whisk until well combined. This batter will help the seasoned flour adhere to the onion petals.

Dip each petal first into the batter to coat it fully. Next, move the coated petal into the seasoned flour, pressing it to ensure it sticks. For an extra crispy finish, repeat the process by dipping back into the batter and then once again into the flour.

In a deep skillet or fryer, heat oil to 350°F (175°C). Careful now—this is hot oil. A good rule of thumb is to test a small piece of onion in the oil; if it sizzles, you're ready.

Gently place a handful of prepared petals into the hot oil. Avoid overcrowding. Fry the petals for about 3-4 minutes or until they are golden brown. Remove and let them drain on paper towels.

Once all your petals are fried, serve them hot with the Bloomin' Sauce on the side. Enjoy the crunchy delight while reminiscing about those unforgettable Arby’s moments!