- Cut the beetroot into small chunks. Wash and peel the potatoes, cut into 4-5 cm chunks and boil in salted water for 10 minutes. Add the beetroot to the pot with the potatoes, return to a boil and cook for another 10 minutes until the potatoes and beetroot are tender. In a separate pot, bring the milk to a boil along with the butter. Drain and mash the potatoes and beetroot, then stir in the milk mixture and season with salt and pepper.
- Preheat the oven to 200°C (190°C convection oven) and grease an oven-proof casserole dish with butter.
- Rinse the fish fillets in cold water and dry carefully, then salt and place them in the greased baking dish. Peel and finely dice the apples, then sprinkle with lemon juice. Remove the thyme leaves from the stems and chop the leaves finely.
- Peel the onions. Dice them finely and sauté in a pan in the remaining butter over a low heat for 10 minutes until light brown. Then add the apples, thyme and mustard. Pour the mixture over the fish and bake for 10 minutes.
- Boil the broccolini in lightly salted water for 2-3 minutes, pour of the water and let steam for 2 minutes with no heat.
- Finely chop the almonds and toast in a dry pan. Slice the green apple.
- Serve with the beetroot-potato puree and wild herb salad, sprinkle with almonds and garnish with the apple slices.