Prepare the Scallops: Remove the side muscle from the scallops. Place them uncovered on a plate in the refrigerator for at least 1 hour to air dry. Remove from the refrigerator 15 minutes before cooking and season lightly with salt.

Sear the Scallops: Place a stainless steel skillet over medium low heat and preheat for 4 minutes. Increase heat to medium high and heat for 2 more minutes. Add enough olive oil to lightly coat the pan. Sear the scallops on one side only for about 3 minutes until a deep golden crust forms. Remove scallops from the pan and set aside.

Build the Sauce: Reduce heat to medium. Add the shallots, onion, and champagne vinegar to the same skillet. Saute for 2-3 minutes until softened. Add the butter and let melt, then sprinkle in the flour and cook for 2 minutes, stirring constantly. Pour in the white wine, add the thyme sprig, and any liquid released by the scallops. Simmer until reduced by about one third, about 5 minutes. Stir in the heavy cream, nutmeg, white pepper, and a pinch of salt and simmer for 2 minutes. Then, add the honey and 3 ounces of the gruyere and stir for another 2 minutes.

Assemble and Broil: Preheat the broiler. Divide the sauce evenly among 6 scallop shells or small baking dishes, filling each about halfway. Top with half of the remaining cheese. Place the shells on a baking sheet and broil on the middle rack for 2 minutes until bubbling. Remove from the oven, place 3 scallops into each shell, and top evenly with the remaining gruyere. Return to the broiler and cook for 3-4 minutes until the cheese is melted and lightly golden.Sprinkle with chives and serve immediately with lemon wedges.