Spread butter over 1 side of each bread slice. Place 1 slice cheese on each unbuttered side of bread. Toast bread, butter side down, in a large skillet or electric griddle over medium-low heat until golden brown, 4-5 minutes.
Layer 1 toast with lettuce, tomato, turkey and avocado. Top with another toast and spread with blue cheese spread. Top with chicken, ham, bacon and egg. Top with remaining toast, cheese side down. Cut sandwich in half, secure with toothpicks and serve.