Chop up the carrot and pickle.
Open and drain the tuna.
Add the tuna, mayo, carrot, pickle, mustard, lemon juice, vinegar, parsley, and salt together in a bowl.
Preheat oven to 350. Toast 4 slices of bread. Place on a baking sheet and put the tuna spread on. Top with cheese and tomato. I don't care for tomatoes, but my wife does.
Butter the bread if desired. Cook for 6-7 minutes or until the cheese is melted.
Serve hot with Fritos and lemonade. Easy and delicious.