Peel outer skins from Vidalia onions. Pierce each top to bottom with fork tines 6-8 times using fork for steam vents.
Fill large pot water halfway. Add 1 tsp salt from measuring spoon. Bring boil high heat. Drop onions in, boil uncovered 40-45 minutes till fork pierces center easy.
Drain pot. Run cold water brief to handle. Slice each onion half top to bottom using knife, keep layers intact on plate.
Pry layers slight with fork tines. Stuff 1 tbsp softened butter per half using measuring spoon. Sprinkle salt, pepper, garlic powder from measuring spoons.
