For the spiced mussel soup, if any mussels are opened, tap them lightly on a hard surface. If they don't close, discard them.
Put the mussels in a saucepan, add the white wine and cook for 3-4 minutes. Drain, reserving the cooking liquor, and discard any closed mussels.
Pick most of mussels from their shells, keeping some in their shells for the garnish. Discard the shells.
Heat a large frying pan and add the oil. Add the shallot, garlic, fennel and curry powder and cook for 3-4 minutes.
Add the stock, three-quarters of the mussels and the cream.
Cook for a further 3-4 minutes, until warmed through, then blend with a stick blender until smooth. Season with salt, pepper and lemon juice, to taste.
Melt the butter in a large frying pan. Once hot, add the carrot, fennel and leek and cook for 2-3 minutes. Add the mushrooms and cook for a further two minutes.
Meanwhile, for the griddled toast, heat a large griddle pan until hot. Drizzle the sliced bread with oil. Toast the bread on the griddle for 2-3 minutes.
To serve, pile the cooked carrot, fennel, leeks and mushrooms in the centre of shallow serving bowls and ladle the blended soup around the edge.
Garnish with a swirls of olive oil, coriander cress and the reserved mussels. Place the griddled toast on the side.