Remove scallops from shells and coat with 15ml of olive oil.
Grill scallops for 30 seconds per side and return to cleaned shells.
Coat chicory with remaining oil and grill for 3 minutes until tender.
Boil vinegar and peppercorns in a pan until reduced to 15ml.
Strain the liquid and discard the peppercorns.
Blend egg yolks while slowly adding vinegar reduction and melted butter.
Fold in mustard and season the sauce with salt and pepper.
Preheat the grill to a medium temperature.
Top scallops with hollandaise and grill for 2 minutes until bubbling.
Serve scallops immediately over the chargrilled chicory.