In a saucepan, combine rice with 1 cup of water and a pinch of salt and pepper. Cover and bring to a boil. Once boiling, turn heat down to low and let simmer for about 45 minutes. When all of the water is absorbed, fluff it with a fork and set aside.
Preheat oven to 350 degrees.
In a large bowl, combine the cooked rice, beans, tomatoes, onions, cumin, chili powder and garlic. Stir to combine.
To prep the poblanos, cut the ends off and then carefully cut them lengthwise to separate in half. Remove the seeds and carefully spoon the rice mixture into the poblanos until they are completely full.
Place the stuffed poblanos on a baking sheet and bake for about 35-40 minutes, until the poblanos are soft.
In the meantime, make the sauce by combining all of the sauce ingredients in a bowl and mash with a fork until smooth. You could also do this in a food processor.
When ready to serve, plate the poblanos and top with the avocado sauce.
Notes
*you could also use dairy-free sour cream instead of yogurt