Position a rack in the middle of the oven (4-6 inches from heat element). Preheat broiler and line a baking tray / sheet with foil.
Thaw out lobster tails, if frozen, in a pot of cold water for 30 minutes or more, until fully thawed. Rinse and pat dry with paper towels.
In a small saucepan, melt the butter over medium heat. Add the garlic and sauté until fragrant (about 1 minute), then add the white wine. Allow to simmer and let reduce slightly (about 2-3 minutes), then add the honey, lemon juice, salt and pepper. Whisk until the honey has melted through the butter and the mixture is well combined. Set aside.
Using sharp kitchen shears, cut the top shell down the centre of the back to the end of the tail, leaving tail fan intact. Remove vein or shell shards, if any. Run your finger between the meat and the shell to loosen it. Spread the meat slightly open. Pull and lift the lobster meat off of the bottom of the shell, being careful not to pull the tail out completely. Place an onion wedge beneath the meat (between the meat and the shell).
Place lobster tails, meat side up, on baking sheet. Set aside. Sprinkle each lobster with a pinch of salt and a little pepper (If desired).
Using half of the sauce, pour or brush over each lobster (concentrating on the meat) and reserve the remaining sauce for serving.
Broil for 12 to 14 minutes or until lobster meat is opaque, and edges are slightly charred.
Garnish with parsley and serve immediately with the remaining sauce and lemon slices.