Steps
1. In a bowl, mash the avocado with a fork until creamy.
2. Add finely chopped onion, mayonnaise, ketchup, mustard, salt, and pepper to the avocado and mix well.
3. In a separate bowl, mix the drained tuna with a pinch of salt and pepper.
4. Combine the tuna mixture with the avocado blend gently.
5. Heat oil in a small pan over medium heat.
6. Lightly beat the egg with milk and a pinch of salt.
7. Toast the bread until golden brown.
8. Pour the egg mixture into the pan and cook a thin omelette or scrambled egg.
9. Spread the tuna-avocado mixture evenly on the toasted bread.
10. Place the cooked egg on top of the mixture.
11. Optionally, add a sprinkle of pepper or extra seasoning to taste.
12. Serve immediately and enjoy!