Bagel with Adriatic Queen tuna pate

1. Cut the bagel in half and, if desired, lightly toast it in a pan or in the oven until crispy.
2. Brush the bottom half with butter or olive oil if desired.
3. Place a lettuce leaf on top, then carefully spread the tuna pate, cut the tomato into rings and add them, and if desired, thin slices of avocado and a slice of cheese.
4. Season with salt and pepper to taste, then cover with the top half of the bagel.
5. You can serve the sandwich immediately or bake it briefly in the oven or on a pan with a lid so that the cheese melts nicely.