Whisk egg yolk, mustard, honey, and vinegar in a bowl.
Gradually whisk in vegetable oil until a thick dressing forms.
Stir in the banana shallot, garlic, and herbs, then season and set aside.
Preheat the grill to its highest setting.
Grease a tray with butter, season it, and arrange salmon slices on top.
Simmer shallot, vermouth, and wine in a pan until reduced by half.
Add double cream and simmer until the sauce thickens slightly.
Season the sauce and stir in the sliced sorrel.
Grill the salmon for 2-3 minutes until just cooked through.
Plate the sauce first, top with salmon, and serve with dressed salad.