You can also add a dozen mushrooms, sliced, to the sautéed onions for even more flavor

Begin by washing potatoes; dry; rub with oil or butter; prick skins with a fork. Bake potatoes at 400 degrees F for 1 Hour or until done. Remove from oven and cool slightly.
Heat butter in a small frying pan. Sauté diced onions in hot oil until just translucent. Set aside.
Cut off a long thin slice off one side of the potato and scoop out the flesh. Place in a large bowl. Add the sautéed onions. Add sour cream or Greek yogurt. Add kosher salt to taste. Mix potatoes until smooth and creamy. Spoon potato mixture back into the potato skins. Alternately, you can put the mixture into a piping bag fitted with a large star tip like 827, and pipe the potatoes back into the shell.
Return the potatoes to the oven and bake 15 Minutes or until filling is crisp. Serve immediately.
