In a bowl mix rice, tomatoes, celery, gherkins, yogurt and cheese. Add salt and pepper. Cut avocados in half, remove pits and fill cavities with rice mixture. Serve at once. Makes six portions.
Cook’s note: I provide grapefruit spoons when serving this dish so every morsel of the avocado can be scraped out of the skin. You don't really need places. Just hand them around in napkins.