Wash and clean the tomatoes, leaving a little green in the process. Cut the top off the tomatoes. Spoon out the tomato pulp and chop finely. Carefully peel the skin from the avocado. Cut the flesh into small cubes. Peel and finely chop the onion. Wash the dill, shake dry, pluck the little flags from the stalks and cut finely.
Drain the tuna, mix with avocado, onion, dill, tomato pulp and mayonnaise, season with salt and pepper. Stuff the tomatoes with it and arrange in a sealable container. Serve with slices of mango, raspberries, blueberry and cooked sugar snap peas with a cream cheese dip