Cooking instructions
- Heat your oven to 200˚C/180˚C fan/gas mark 6.
 - Peel and cut the potatoes into quarters then put them into a large saucepan. Cover them with cold water and put the pan over a medium heat. When the water is boiling, turn down to a simmer and let the potatoes cook for 15 to 20 minutes until they are very soft.
 - Drain the potatoes in a colander, then put them back into the pan and mash them with a potato masher. Add the butter and milk to the pan and mash again until the potatoes are lovely and smooth.
 - While the potatoes are cooking, slice the spring onions into small rings. Then chop the parsley with a large knife or in a mug with a pair of scissors.
 - Grate the Cheddar cheese, being careful not to grate your fingers!
 - Place the flame-proof casserole dish over a medium heat and add the butter for the filling. When it has melted, add the spring onions and fry for a minute or so.
 - Add the peas and the mustard and cook for another minute, stirring.
 - Add the milk and crème fraîche and gently simmer for 5 to 10 minutes until it thickens a little bit. Then add the cheese and give it a good stir.
 - When the cheese has melted, add the pieces of fish and cover them with the sauce. Stir in the chopped parsley and remove from the heat. Season with a little salt and pepper and stir again.
 - Spoon the mash on top of the fish mixture and spread it out to cover the whole top. Use a fork to make a wavy pattern on the top to look like the ocean but don’t press too hard so you don’t push through.
 - Put the dish into the oven for 20 to 25 minutes until bubbling around the edges and crispy on top.
 - Serve in bowls with extra veg on the side. How warming is that?
 
Extracted from Matilda & The Ramsay Bunch: Tilly’s Kitchen Takeover by Tilly Ramsay
Published by Hodder & Stoughton on 4th May 2017
Priced: £20
Pictures ©Jemma Watts
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