Step 1 of 7:
Clarify buttermilk: Place buttermilk in a pot and heat until it boils and the protein and whey separate. Strain the whey through a fine sieve or cheesecloth. Use the drained whey (= clarified buttermilk) for the sauce, discard the solid residue.
Step 2 of 7:
For the white wine reduction: Reduce white wine, shallot, and bay leaf in a pot by about half. Strain through a fine sieve and set the reduction aside for the sauce.
Step 3 of 7:
Prepare Beurre Blanc: Combine clarified buttermilk, white wine reduction, and caper water in a pot, season, and bring to a boil once. Then remove the pot from the heat. Incorporate the cold butter with an immersion blender until a stable emulsion forms. Optional: For more binding, mix some cornstarch with cold water, stir it in, and briefly bring to a boil, then blend in the butter. Keep the sauce warm only, do not boil again, otherwise the emulsion will separate.
Step 4 of 7:
Fry capers: First, thoroughly pat the capers dry. Heat the oil in a small, tall pot to 160–180 °C. Fry the capers until they pop open and are crispy. Drain on paper towels.
Step 5 of 7:
For the cauliflower mash, divide the cauliflower into florets (set some aside for pickling). Cook the remaining cauliflower in salted water until soft, drain well. Roughly mash with cream and butter (do not puree). Season with salt and miso. For serving, gently fold in finely chopped chives.
Step 6 of 7:
Confit salmon: For the brine, bring water with 5% salt to a boil once, let it cool completely. Cover the fish completely with the cold brine and let it steep for approx. 15 minutes, depending on thickness. Remove, rinse briefly, and pat dry. Preheat oil in a suitable dish in the oven to 55 °C. Cover the fish completely with oil and confit at 55 °C for 10–15 minutes. Doneness test: Insert a thin skewer – if it glides through without resistance, the fish is perfect. Neither undercooked nor overcooked.
Step 7 of 7:
Plating: Place the cauliflower mash in the center, arrange the confit fish on top or next to it. Add chives and caviar (optional) to the buttermilk-caper beurre blanc and pour onto the plate. Distribute pickled cauliflower florets and fried capers over the fish. Enjoy your meal!