In a medium bowl, whisk together all the marinade ingredients.

Add the chicken and submerge. Cover and refrigerate for at least 20 minutes, up to 3 hours.

Meanwhile, preheat the oven to 400 degrees F. Line a baking sheet with foil or parchment paper.

Cut the tops off the red and yellow bell peppers and scoop out the seeds. If the bell peppers don’t stand up straight, you can cut the bottom slightly to create a flat surface, but don’t cut so much that there is a hole on the bottom. Place the peppers standing up on the baking sheet.

Brush the insides of the peppers with olive oil. Season very lightly with sea salt.

Roast the peppers in the oven for about 20 minutes, until soft and golden on the edges.

When peppers are done, use paper towels to blot any liquid from the inside.

While the peppers are roasting and chicken is marinating, heat 1 tablespoon oil in a large saute pan over medium-high heat. Add the green peppers and onions. Season with sea salt and black pepper. Saute until soft and browned, about 7 to 10 minutes.

Add the garlic and saute for about a minute, until fragrant. Transfer to a bowl, cover and set aside.

Heat another tablespoon oil in the same pan over medium-high heat. Shake off the excess marinade from the chicken and add the chicken to the pan. Cook until browned on the bottom and opaque on the edges, about 7 to 10 minutes. Flip and repeat on the other side, until cooked through.

Let the chicken rest for 5 minutes, then slice and mix with the veggies.

Spoon the fajita evenly inside the peppers. Garnish with fresh cilantro, if desired. (Check the post above for more garnish & topping ideas!)