1. Preheat oven to 425°.
2. Combine first 3 ingredients in a bowl. Spoon tuna mixture evenly over toasted bread slices. Top tuna mixture evenly with bacon, avocado, and cheese. Place sandwiches on a baking sheet.
3. Bake at 425° for 2 minutes or until cheese melts.
Serve with: Spicy Sweet Potato Fries