Finely chop the crab meat.

Finely slice the spring onion, reserving a few slices for garnish.

Grind the walnut halves.

Grind the linseeds.

Mix the crab meat, spring onion, ground walnuts, ground linseeds, flour, egg yolk, and mayonnaise in a bowl.

Season the mixture with a little salt.

Shape the mixture into 4 small, flat patties.

Heat oil in a small non-stick pan.

Sear the crab cakes in the hot oil, turning occasionally, for 5 minutes until golden brown.

Remove the crab cakes from the pan and set aside to cool slightly.

Serve the crab cakes with sliced lemon and reserved spring onion garnish.