In a large bowl, combine the ground chicken with the thyme, cumin, marjoram, garlic salt and juice of half a lemon. Mix thoroughly until the seasonings are evenly distributed throughout the meat. Mix in the parsley.
Lay out the mini tortillas and spoon a rounded tablespoon of the chicken mixture onto each one. Press down firmly to spread the mixture evenly across the surface of the tortilla.
Heat a large pan over medium high heat and coat with about a teaspoon of oil. Place one of two tortillas on the pan, chicken side down. Cook for about three minutes or until the chicken is golden and slightly crispy. Lower the heat to medium low and cook for an additional 2 minutes.
Flip the tortillas over and cook for another minute to ensure the chicken is cooked through. Add more oil if necessary for the remaining tortillas.
Remove the tortillas from the pan and place on a plate covered with foil to keep them warm.
To serve: top each tortilla with a generous dollop of tzatziki sauce, tomatoes, cucumbers, and red onions. Garnish with fresh parsley and a squeeze of fresh lemon if desired.