Shell shrimps except for tail part. Split front lengthwise into halves and flatten them with a cleaver, pat dry. Put one slice of bacon onto each shrimp. Set aside for later use. Set wok over high heat until hot. Put in 2 tablespoons cooking oil and the sliced onions. Stir fry for 2 minutes or until the onions are soft. Add in 1 tablespoon thin soy. Mix well. Remove onto serving platter and set aside for later use. Heat wok until hot. Add 4 tablespoons oil. Dip each shrimp into the beaten eggs and pan fry the side with the bacon for 2 minutes over medium heat. Flip over and fry another 2 minutes or until golden. Remove and arrange on top of the onions. NOTE: Pan frying may be done by rolling wok to coat the sides with oil and placing the shrimp along the sides of the wok. Heat wok again. Use the same oil left from frying the shrimp. Put in garlic and sauce mixture. Bring to a boil and stir in cornstarch to thicken. Pour it over the butterfly shrimp.