Combine your tomatoes, dill, onion, and black pepper (if you’re using it) in a bowl, and toss to create a simple salad.
Put each of the lunchbox components—the salad, the chicken, the avocado, and the celery sticks into different compartments in a container, or into small separate containers.
This meal is designed to be enjoyed picnic-style. When it comes time for lunch, it’s as easy as assembling the different pieces on the crispbread, or enjoying them on their own.
Hint: If you’re taking this to work with you, a squeeze of lemon juice stirred through the avocado will help prevent it browning before meal time.