Pastrami tastes best when sliced thinly and served at room temperature. So take the pastrami out of the fridge about 30 minutes before serving. It will taste extra tender and aromatic. Set the pastrami aside.

Preheat the oven or air fryer to 180°C.

Cut the onion into fine rings and fry in a little oil over medium heat until crispy.

In the end, caramelize with sugar.

In the meantime, mix the cream cheese with the mustard and cut the rye bread into slices.

Grate the cheese and sprinkle it on the top halves of the bread.

Place in the oven/air fryer with the bottom halves and bake for 3-4 minutes.

Next, spread the bottom slices of bread with the mustard cream and top them with a thick layer of pastrami slices.

Spread the roasted onion on the upper half and place all the bread slices on top of each other.