Lay out 4 slices of potato bread. Spread a thin layer of sour cream onto each slice of potato bread. Top each slice of potato bread with a slice of sharp cheddar cheese. Place bacon onto two of the slices of bread (one half of each sandwich). Sprinkle each slice of potato bread with chopped green onions.
Put the sandwiches together. Spread butter onto the outsides of both sandwiches
Place on the griddle and cook until golden brown and the cheese is melted. Remove the sandwiches from the hot griddle and set on a cooling rack for a few minutes. (This helps the bread to not become soggy). Serve.