For the plaice fillets with potato-herb puree, peel the potatoes and boil them in salted water. Then strain them and let them cool down.
Heat milk, butter and whipping cream together in a saucepan and add to the potatoes. Roughly break everything up with a potato masher (it should not become a puree!) and add the liquids.
Remove potatoes from heat and add more liquid as needed. Then fold in coarsely chopped herbs and season with salt, olive oil and nutmeg.
Turn the salted and peppered plaice fillets in flour and sear them on both sides in the olive oil/butter mixture.
Serve the plaice fillets with mashed potatoes and herbs.