Shred the crab sticks finely. To make it easier, place them in a plastic bag and rub them until separated.

Finely chop the onion. If you dislike the sharp taste of raw onion, soak it in cold water briefly before using.

Mix the shredded crab sticks, chopped onion, 2 tbsp mayonnaise, 1 tbsp mustard, and 1/2 tbsp sugar in a bowl.

Toast the bread slices in a dry pan until crispy.

Spread the crab stick salad generously on one slice of toasted bread.