BEREIDING

1. Peel the potatoes and celeriac. Cut into equal pieces and add to a pan of cold water. Bring to the boil, then lower the heat and cook for 20-30 minutes until the potatoes and celeriac are tender. Drain and leave to dry steam for a few more minutes with the lid on. Heat a dash of milk with a good knob of butter in a saucepan. Mix this with the potato and celeriac with a generous pinch of salt and pepper and mash into a puree. You can make the puree in advance and heat it up in the microwave at the last minute, possibly with an extra knob of butter.
2. Cut the radicchio into quarters or into 8 parts depending on the size. You want thin segments. Wrap the segments with the pancetta and grill them in a dry griddle pan until the pancetta is golden brown. Sprinkle with a little balsamic vinegar. You can also prepare this in advance and heat it up last minute in the oven.
3. In the meantime, make the miso beurre blanc. Slice the shallot into rings and add these to a small saucepan with the mirin, white wine and miso. Bring to the boil and let it cook for a couple of minutes, stirring regularly. Strain the shallot from the mixture and pour the liquid back into the pan. Turn the heat down and add cubes of the cold butter one by one, stirring with a whisk until they are nicely dissolved. Note: you cannot reheat beurre blanc, otherwise the sauce will separate. So make sure it stays at the right temperature (around 40-50 degrees), possibly in a warm water bath if the fish is not ready yet.
4. Cut incisions in the skin of the fish. Melt a knob of butter in a large frying pan and fry the fish on the skin until it is almost cooked, this way you get a crispy skin. Flip and fry the fish for another 30 seconds on the other side.
5. Spread a large spoonful of puree over each plate. Place the sea-bream on the puree and the grilled radicchio next to it. Finish with the miso beurre blanc and a sprig of fresh thyme and serve immediately.