Preparation Mix cheese and chopped watercress in medium bowl. Season with salt. Spread mixture evenly over 8 bread slices. Top with remaining bread. Butter edges of sandwiches. Cut sandwiches diagonally in half. Place pecans on plate. Dip buttered edges of sandwiches into pecans. Arrange sandwiches on platter. Garnish with watercress sprigs. (Can be made 8 hours ahead. Cover sandwiches tightly; chill.)
Preparation Mix cheese and chopped watercress in medium bowl. Season with salt. Spread mixture evenly over 8 bread slices. Top with remaining bread. Butter edges of sandwiches. Cut sandwiches diagonally in half. Place pecans on plate. Dip buttered edges of sandwiches into pecans. Arrange sandwiches on platter. Garnish with watercress sprigs. (Can be made 8 hours ahead. Cover sandwiches tightly; chill.)