1. Peel the onion and dice it very finely. Dice the pickled gherkin very finely as well. Mix both together with the mayonnaise, Sriracha sauce, and mustard in a small bowl. Season with salt and pepper to taste.

2. Spread some butter on one side of each bread slice – olive oil works as an alternative just as well. Flip the bread slices over and spread the sauce onto two of the bread slices. Place the pastrami on top of the sauce, then add the cheese and top with sauerkraut. Place the plain bread slices – buttered side up – on top of the sauerkraut and place the sandwiches in the Air Fryer basket. We use baking parchment here to keep the Air Fryer as clean as possible.

3. Set the Air Fryer to a temperature of 160°C (320°F) and toast the sandwiches for 6–8 minutes. Flip the sandwiches over halfway through the cooking time. Remove them from the Air Fryer. Add a small pickle to each sandwich with a wooden skewer (optional), then serve the sandwiches immediately.