Peel the parsnips and dice. Peel the shallot and garlic and cut finely. Heat the butter in a small pot. Sauté the parsnips, shallot and garlic with the garam masala for a few minutes, season with salt and pepper. Pour in the cream and cook until soft. Refine with the lemon zest and juice and blend. Keep warm.
Peel the shallot and garlic and cut in half. Add to a small pot along with the white wine, stock and thyme, and leaving 2 tablespoons, boil down until it looks like syrup. Take out the shallot, garlic and thyme. Stir the sepia ink and butter into the liquid with a whisk. Thicken the sauce by stirring in cornflour mixed with some cold water (about 2 tablespoons). Season with salt and pepper and keep warm.
In the meantime, peel the turnips and cut into quarters. Add to a pot along with the butter and vegetable stock. Season with salt, pepper and sugar, then cover and cook until soft. When nearly cooked, remove the lid to let the liquid boil away.
Salt the zander and heat the clarified butter in a pan. Fry the skin side until crispy, turn the fish over and let it sit in the pan for a few minutes.
Cut the fermented garlic cloves in half lengthwise.
Arrange the purée onto the plates and top with the fried zander. Scatter the turnips and garlic around it, drizzle the sauce around it and serve immediately.