Wash the herbs and shake dry. Pluck off the herb leaves and rosemary needles. Wash the limes hot, dry them and finely grate the peel. Peel and chop the ginger and garlic. Cut the chillies lengthwise, remove seeds, wash and cut into very fine rings.
Puree the herbs, lime zest, ginger, garlic, chilli, 1 tsp. paprika powder, 1 tsp. salt, peppercorns and 80 ml olive oil in a kitchen blender to a medium-fine paste.
Cut the shrimps lengthwise along the back and remove the dark intestine. Rinse prawns, dab dry and let them steep in the spice paste. Heat 2 tablespoons of oil in a frying pan and fry the baguette in it until golden brown on each side.
Heat a grill pan very strongly and fry the prawns with the paste in it for 2-3 minutes. Arrange on the baguette.