Step 1

For the Tzatziki Sauce: Combine all ingredients and stir well. Refrigerate until ready to serve.

Step 2

Remove any large pieces of fat from the beef roast and then slice the meat into thin, 1/4 inch strips. Place in the bottom of the slow cooker. 

Step 3

In a small bowl combine the olive oil, garlic powder, oregano, cumin, thyme, lemon juice, salt, and pepper. Pour over meat. Cover and cook on LOW for 6 hours or until beef is tender.

Step 4

Add a lettuce leaf to a pita. Top with meat, tomatoes, cucumber, onion and tzatziki sauce.

Step 5

Remove any large pieces of fat from the beef roast and then slice the meat into thin, 1/4 inch strips. Place in Instant pot.

Step 6

In a small bowl combine ⅓ cup of WATER, olive oil, garlic powder, oregano, cumin, thyme, lemon juice, and salt and pepper. Pour over meat.

Step 7

Cover and turn the valve to "sealing." Press "manual" or high pressure, and set the timer for 30 minutes.

Step 8

After the timer beeps allow the instant pot to rest for 15 minutes before releasing any of the pressure. Remove the lid, taste, and add additional seasonings if needed.

Step 9

Add a lettuce leaf to a pita. Top with meat, tomatoes, cucumber, onion and tzatziki sauce.