Add all of the yogurt dressing ingredients to a food processor or blender. Pulse until smooth. Taste and adjust seasonings as needed. Set aside.
Heat the oil in a skillet over medium-high heat. Add the bell peppers, onion and dry seasonings. Toss to coat and cook until charred and tender (approx. 5 minutes). Remove from the heat.
To serve, add rice to each bowl and top with fajita veggies, beans, corn, tomatoes and avocado. Drizzle with the dressing, top with cilantro and serve with lime wedges on the side.