4 medium onions
6 slices of gouda
2 large pickled gherkins
For the coating
1 3/4 cups plain flour
1/2 teaspoon salt
1/2 teaspoon white pepper
1 cup water
1 1/2 cups breadcrumbs
4 cups vegetable oil, for frying
1/4 cup mayonnaise
1 tablespoon drained horseradish
2 teaspoons ketchup
1/4 teaspoon Cajun seasoning
Slice off 1/2 inch from the top and bottom of an onion, then peel it and slice it in half across the middle. Take off the outer ring and remove any membrane. Pair it with a smaller ring that fits inside but leaves a small gap. Repeat with more onions until you have 8 sets of rings, then put them all onto a tray.
Cut strips of cheese and insert them between the two rings of onion. Cut slices of gherkins to fit in the middle of the rings; wrap this in a strip of cheese and insert that into the middle. Use extra bits of cheese to fill any gaps.
Mix together the flour, salt and pepper, then break in the eggs and whisk together. Gradually add the water and whisk until smooth. Put the breadcrumbs into a shallow dish and line a tray with baking parchment.
Working with one at a time, submerge the onion rings in the batter then lift them out with two forks. Transfer them to the breadcrumb dish and spoon breadcrumbs all over them. Put the coated ring back into the batter and then the breadcrumbs, to give them a double coating, then shape them with your hands so they are smooth. Put them onto the lined tray and then into the freezer for one hour.
Make the tangy sauce: In a small bowl, add the mayonnaise, horseradish, ketchup and Cajun seasoning and whisk together with a fork.
Cook the onion rings: Preheat the oven to 350 degrees. Heat the oil in a large saucepan, big enough that the oil doesn’t come more than halfway up the inside. The oil is ready when it reaches 350 degrees.
In batches, lower the onion rings straight into the hot oil and cook for 3 minutes, until golden brown. Drain on paper towels. Once they’re all golden brown, put the onion rings onto a tray and into the hot oven for 10 minutes to cook through. Serve immediately, with tangy sauce on the side.