Add the olive oil to a medium skillet over medium high heat. Once the olive oil is hot, add the onions and cook until soft and translucent. Add in the chicken and mix with the onions, then add the sumac, salt and pepper and cook for one minute. Remove skillet from heat.

Preheat the oven to 350F

In a 9×13 baking dish, add the vegetable oil to the bottom, spreading throughout the bottom of the dish. Fill each tortilla in the corner facing you with about 2 tablespoons of the chicken mixture. Roll the tortilla, slightly tucking under and place into the 9×13 baking dish with the fold side down. Finish rolling each tortilla and placing them into the dish. Flip around each tortilla in the dish once to coat it with the oil from the bottom, making sure the fold is still tucked underneath.

Bake the whole dish for 30 minutes or until golden brown. Let cool 5 minutes and serve with yogurt and if you enjoy spicy foods, add pickled jalapenos on the side. Enjoy!