In a large bowl, mix all of the burger ingredients together. Divide into 4 and shape your burgers, making them about 1/2” thick.
Set your grill to medium-high. Grill your burgers for about 5 minutes per side. Add the halloumi cheese to the grill and cook about 2 minutes per side or until you have dark grill marks.
Stuff each pita half with a burger, some cheese and all of the toppings you like. Enjoy.