Firstly, lay the ingredients out to make the rosti mixture.
Now, do the same for the ingredients for the remainder of the dish.
Next, peel and roughly grate the potatoes. Then squeeze thoroughly to remove as much of the water as you can.
Now, add the onion, garlic, cumin, and seasoning to the dry grated potato and mix thoroughly.
Cook the rostis by firstly heating a pan over a medium heat with olive oil. Using rosti rings cook the rosti for 4-5 minutes on each side until golden brown and soft in the middle.
At the same time as cooking the rosti, pan fry the cod in olive oil and butter for 3 minutes each side. The fish is cooked when flaky and hot in the middle.
When the fish is almost done steam the samphire for 3 minutes. Do not season.
Finally, make the beurre blanc sauce by reducing the wine and shallots by 2/3 and then whisking in the butter one cube at a time. Finish with a little seasoning and an optional 1 teaspoon of lemon juice. Pass through a sieve and serve.
Now construct the dish by firstly placing the cod on top of the rosti.
Add the samphire.
Finally, drizzle a little of the beurre blanc sauce over the dish.
Serve immediately and enjoy! Yum Yum!!