Melt 2 Tbsp. butter and use to lightly brush both sides of bread slices. Put on baking sheet and toast under broiler for 1 to 2 minutes or til golden brown.
Heat 2 Tbsp. butter and olive oil in saute pan over high heat and cook onions for 8 to 1 minutes or til lightly caramelized. Keep warm.
Saute crabmeat in 1 Tbsp. butter. Keep warm. Make Bearnaise sauce according to packet directions.
Put 1 bread square on each plate. Top with a beef filet, then another square. Add crabmeat and another square. To with onions. Spoon on Bearnaise sauce and garnish with a sprig of tarragon and a sprinkle of paprika on the plate rim. Makes 4 servings.