Preheat oven to 375°F. Remove lamb roast from packaging. If the roast comes in a net, remove that as well. Pat dry and set aside.
Combine spices in a medium sized bowl. Generously rub spice mix over entire lamb roast. Place roast on a lipped baking sheet or in a roasting pan. Tuck the 'tail' piece (small thin end) under the roast.
Cook for 1 hour, roast should be medium well to well done. Let cool 15 to 20 minutes. After the roast has rested, use a sharp knife to slice the lamb roast in very thin pieces, ¼" to ⅛" thick.
While the roast is resting, prepare the remaining ingredients.
In a small bowl, combine yogurt and fresh chopped mint. Mix well.
Chop tomatoes and cucumbers. Julienne lettuce.
Using either the microwave on lowest setting or a gas stove, warm pita bread. If using a gas stove top, turn on the lowest heat setting and carefully toast the pita on both sides for about 15 to 20 seconds.
Create your own personalized gyros, with your favorite combination of toppings!