Prepare the rice: cook rice in a saucepan or rice cooker with 3 cups of water or according to package instructions.
Make the chipotle dressing: mix the yogurt, vegan mayonnaise, lime juice, smoked paprika, chili powder, and adobo sauce in a small bowl, adding water if needed to achieve desired consistency.
Heat avocado oil in a large skillet over medium heat. Add sliced onions and pepper; cook while stirring occasionally until soft and tender, about 7-10 minutes, adding a splash of water if needed to prevent vegetables from burning. Then add your black beans, corn, along with the seasonings; cook for an additional 2-3 minutes until corn is warmed through but still retains some crunch. Set aside.
Assemble your bowls: divide the cooked rice between 4 bowls or containers. Top rice with fajita mixture, and top with any toppings of choice. Drizzle the chipotle dressing right before serving. Leftovers can be stored in airtight containers in the fridge for up to 3 days.