(edited - it's not in the book. Sorry, I thought it was. However, you can find it on his Instagram thingy and also here on you tube https://www.youtube.com/watch?v=8W5DKUOVUhU - sorry)
However, I adapted it quite a lot so I can take a little of the credit for it.
Amounts below are for one.
some frozen peas
2 sheets of lasagne
one mushroom, finely chopped
quarter of a small-ish onion, finely chopped
small splash oil
1/12 of a pack of savers soft cheese
quarter of a pint of cheese sauce (I already had some which was leftover and had been frozen)
15g finely grated cheddar cheese. Choose your cheddar carefully. A strong one from a budget shop can be very reasonably priced and the stronger it is, the less you need for the flavour
Turn the oven on to around 180C
Cook the peas and the lasagne sheets in salted water. They take about the same time to cook.
While they are cooking, saute the onion and the mushroom in a very little oil.
When the peas and lasagne are cooked, drain, lay the lasagne flat on a non stick surface (like some baking parchment) and put the peas in a bowl. Add the onion, mushroom and soft cheese and mix well. The soft cheese should melt into the mixture. Add some pepper if you want. Salt is not needed.
Place half the mixture at the end of each lasagne sheet and roll them up, like cannelloni. Carefully place them in an appropriately sized, oiled baking dish.
Pour over the cheese sauce and then sprinkle over the grated cheese. Bake in the oven until all is piping hot and the cheese has browned.