preheat oven to 400˚

cut chicken in roughly 1x2 inch strips, no need to be perfect, if you prefer small pieces just be aware they will cook faster

place chicken in mixing bowl, toss with 1 TBSP oil, and the Shawarma seasoning, mix well and let rest until ready to cook

cut the pepper in roughly 1-inch strips

cut the onion in half and then cut int 1-inch pieces

lightly grease a sheet

toss the vegetables with the remaining oil

spread them out on the sheet pan

add the chicken

sprinkle with one teaspoon of salt

bake at 400˚ for 25-30 minutes or until the chicken is good through

keep an eye on the pan, if your chicken breast were the kind injected with a brine it may get very juicy, you can easily drain off some of the juice if you need to