Crab and leek cakes

Method

1. Cook the potatoes for 25 minutes in a steamer until very soft. Pat dry, then leave to cool completely. (Or boil for 20 minutes, drain well, then return to the pan over a very low heat for a couple of minutes to dry thoroughly.) Leave to cool.
2. Make the mayonnaise by whisking the egg yolks with a small squeeze of lemon juice, mustard powder and seasoning in a bowl. Whisking continuously, gradually add the mild oil in a slow but steady stream.
3. As you whisk, the mayonnaise will begin to thicken. At this stage, slowly whisk in the olive oil. Stop adding oil once the mayonnaise has a thick, glossy consistency. Taste, adjust the seasoning and add more lemon juice if needed. Chill until needed.
4. To make the crab cakes, heat the oil in a small frying pan, then fry the leeks over a low-medium heat for 5-6 minutes until softened. Tip into a bowl and allow to cool.
5. Mash the potatoes with a fork, then add to the cooled leeks with the crabmeat, cayenne and parsley. Season well and shape the mixture into 8 patties. Dip each one in the polenta to coat. Put on a plate and chill for at least 10 minutes.
6. Heat a shallow layer of oil in a large frying pan over a medium-high heat and fry the cakes for 2-3 minutes on both sides until golden brown and hot all the way through. Serve with the mayonnaise, lemon wedges and seasonal veg or, if you prefer, a fresh green salad.