4 tbsp finely chopped chives
1 bulb fennel, cored and thinly sliced
1 garlic clove, peeled and left whole
1 tbsp roughly chopped fresh parsley
4 rosemary sprigs
6 sun-dried tomatoes in oil
1 tbsp fennel seeds
4 tbsp harissa paste
1 tbsp harissa oil, taken from harissa jar
1 tbsp olive oil
salt
4 tbsp crème fraîche
2 medium whole mackerel, gutted, head removed and scored on both sides
1 good-quality French sausage
2 slices baguette