Add 2 tablespoons of oil, chipotle pepper, adobo sauce, garlic, lime juice, red onion, salt, pepper & cumin to a small blender. Blend until smooth.
Heat the remaining oil in a skillet over medium heat. Add the vegan chicken & bell pepper and cook until they start to char, flipping as needed (approx. 5-7 minutes). Add the chipotle sauce and cook for a couple more minutes - the sauce should stick to the chicken and char even more.
While the chicken is cooking, add the aioli ingredients to a bowl and mix until combined. Taste and adjust the seasonings as needed. Set aside.
To assemble, spread some aioli on each pita. Top with romaine, red onion, avocado and the vegan chicken. Serve the leftover aioli on the side.
Video
Notes
I used plain, frozen, un-breaded vegan chicken - the brand is Daring. If you use something different you will want to check the package cooking instructions and adjust as needed. If you don't like vegan chicken you could also use chickpeas.
You could use hummus instead of the aioli for a quicker prep.
These are best served right away, but still taste great if prepped ahead of time.