Finely chop the onion and soak it in water for 5 minutes. Drain and squeeze out excess water.

Cut the salmon in half horizontally and pat dry with paper towels. Season with salt and pepper.

Mix the salmon with mayonnaise in a bowl until evenly coated. Cover with breadcrumbs.

Combine all ingredients for the yogurt tartar sauce in a separate bowl and mix well.

Heat vegetable oil in a frying pan over medium heat. Fry the coated salmon for 1 minute on each side until lightly golden. Remove and cut into quarters.