Put a pot of water on to boil for the pasta. Add salt once it starts to boil.
In a saucepan, reduce the cream slowly over a low heat to 50%, add the beaten eggs and cook them like you are making creamy scrambled eggs stirring all the time until the sauce starts to thicken. Emulsify with a hand blender.
Remove the skin from the trout and cut it into small pieces and fry in butter until it starts to change colour.
Cook the pasta al dente according to the instructions on the packet. Drain it and add it to the pan with the butter and trout. Mix together well with a sprinkling of grated lemon zest.
Pour a little egg cream onto the bottom of each plate and pile the spaghetti and trout on top. Grate some lemon zest over each plate and a little black pepper. Serve immediately.
