Preheat the oven to 350 degrees F.
Cut the avocados in half and remove the pits. Cut 1 avocado open and scoop all the flesh out. Place it in a large bowl. I like to scoop out just a tiny bit of the remaining 4 avocados to create more of a “bowl” and have more room for the chicken, but it’s not necessary. If you scoop a bit out, add it to the bowl.
To that same bowl, add the chicken, 1/3 cup cheese, tomatoes, green onions, cilantro, chili powder, paprika, garlic powder, cumin, salt and pepper. Stir well until combined, making sure to mash the avocado into the mixture to act as a binder and hold the chicken together.
Take an ice cream scoop or spoon and place about ¼ cup (or however much you want!) of the chicken mixture into the cut avocados. Sprinkling the remaining 1/3 cup of cheese over top of the avocados.
Bake for 15 to 20 minutes, until the chicken is warmed through and the cheese is melted. Remove from the oven and drizzle the avocados with the sriracha drizzle. The avocados will get a little dark in color from the baking.
Sprinkle with extra cilantro and greek onions if you wish. Serve immediately!