Melt 1/4 of the 3 Tbsp of ghee in a skillet over medium-high heat, add a mushroom cap, and cook on both sides until completely soft to the center, about 3 minutes
Place cooked mushroom upside down on an aluminum foil-lined baking sheet; sprinkle with garlic powder
Preheat the oven's broiler and set the oven rack at about 6 inches from the heat source
melt the remaining 1 Tbsp of ghee in a skillet over medium-high heat
Add the scallops and cook until just firm, and lightly browned on both sides. Place the scallops on top of the mushroom.
Stir together until the mayonnaise has developed brown patches and is hot ( 3- 5 minutes)
Sprinkle with green onions and serve!
Servings 1