Preheat oven to "Broil" and move the wire rack to the top position in the oven.
Slice the chicken breasts into strips. Line the chicken breasts on a cutting board and slice each breast in half cutting along the short side horizontally creating 4 thin breasts. Then slice against the grain into about ¼ inch strips. Season with salt, pepper, garlic powder and oregano.
Heat a tablespoon of oil in a cast iron skillet over low-medium heat (if you don't have a cast iron pan see recommendations in notes**). Add the chicken breast strips. Allow the chicken to brown on all sides keeping heat relatively low to prevent it from getting over done.
While the chicken cooks, cut the bell pepper and ½ onion in to strips. Peel and mince the garlic cloves. Slice the mushrooms.
Once chicken is cooked, remove the chicken from the pan, drain any excess juices from the pan and set the cooked chicken aside.
Add another tablespoon of oil to the pan and begin adding the onions. Allow the onions to soften and begin to caramelize. Then add the mushrooms and bell peppers. Cook until they veggies become fragrant and then add the garlic. Cook for about 3-4 minutes. Drain any excess water and remove the pan from the heat.
Add the chicken back in to the pan and stir. Pour on the pizza sauce and then top with pepperoni, olives, sliced fresh mozzarella and parmesan. Place in the oven and broil for about 5-10 minutes or until cheese becomes melty and begins to bubble.
Remove from the oven, top with freshly chopped basil and serve.
Notes
** If you do not have a cast iron skillet, any other oven safe pan would work! You can also transfer the skillet meal to a foil boat on a sheet pan and broil like that!You can also use use a regular skillet with a lid. To do this, cook the recipe as written but do not broil. Instead combine all the ingredients back in to the pan, top with cheese, pepperoni and olives and then place the pan on the stove on low heat. Cover with a lid and allow the cheese to melt. The cheese won't get as bubbly as broiled but it will still work.