Clean the mussels by thoroughly scrubbing them under plenty of running water, pulling away and discarding the 'beards', the seaweed-like stringy threads. Discard any broken mussels, and any mussels that don't close tightly when you tap them.
Place the mussels in a saucepan, add the white wine and cook for 3-4 minutes.
Drain, reserving the cooking liquor, and pick the mussels from their shells. Set aside the liquor and the mussels, but discard the shells.
Heat a large frying pan and add the oil. Add the finely chopped shallot, garlic and fennel and cook for 3-4 minutes.
Add the saffron, aniseed liqueur, stock, three-quarters of the mussel meat, finish with the cream
Cook for a further 3-4 minutes until warmed through, then blend with a stick blender until smooth.
Heat a large griddle pan and drizzle the sliced bread with oil and rub with the halved clove of garlic. Toast the bread on the griddle for 2-3 minutes.