In a skillet, fry bacon until crispy but not hard. Drain on paper towel until ready to use.
In a small bowl, whisk together cornmeal & spices; set aside.
Gently dredge oysters in flour then in egg whites & lastly in cornmeal/spice mixture. Cover breaded oysters & refrigerate until ready to bake. Prepare tomato, avocados (guacamole) & bread.
Preheat oven to 375 F.
Remove oysters from refrigerator, spray a baking sheet with cooking spray & carefully place oysters on it so that they are not touching each other. Bake for 15 minutes until crispy & cooked.
Spread bread ‘pieces’ with your choice of dressing. Divide oysters between bottom halves, followed by avocado, bacon & tomato. Place top halves of the bread over the fillings & press lightly. Serve immediately.