1. In a large bowl, mix all arais ingredients into a smooth mixture.
2. Put two tablespoons of the beef mixture into each pita half.
3. Arrange all filled pitas, side by side, in a sealable container. Cover and wrap container in plastic wrap, and refrigerate for up to six hours.
4. To make the techina, blend tahini paste with water, minced garlic, and lemon juice. Season with salt and pepper and transfer to an airtight container.