Place the new potatoes in a sauce pan and cover with water. Season the water with salt. Bring the liquid up to a boil and reduce the heat to medium. Cook the potatoes until fork tender, about 8 to 10 minutes. Place the eggs in a saucepan and cover with water. Bring the water up to a boil and reduce the heat to a simmer. Cook the eggs for 15 minutes after the heat has been reduced. Remove both potatoes and eggs from the water and shock in an ice bath. Remove the potatoes and eggs when cooled and pat dry. Using a paring knife, cut the tip of the potato off on both sides, vertically, so the potato will stand straight up. Using a small melon baller, scoop out the center of the potatoes, leaving about a 1/8-inch shell, reserving the potato scraps. Peel and chop the eggs. In a mixing bowl, combine the reserved potato scraps, chopped eggs mayonnaise, garlic, parsley and onions. Mix thoroughly. Season the mixture with salt and pepper. Season the new potato with salt and pepper. Fill each potato with the potato mixture. Top each potato with caviar and garnish with parsley.