Season the chicken breasts on both sides with garlic powder, onion powder, paprika, and salt, gently patting the seasoning into the meat.
Heat the olive oil in a large skillet over medium-high heat. Add the chicken and cook 4–5 minutes per side, until fully cooked and the internal temperature reaches 165°F. Cook in batches if needed.
Remove the chicken from the skillet and let rest for 5 minutes, then shred using two forks.
In a medium bowl, whisk together the buffalo sauce and Greek yogurt until smooth.
Add the shredded chicken and toss to coat evenly.
Assemble the tacos by layering buffalo chicken onto warm tortillas.
Drizzle with ranch dressing and top with green onions, cilantro, blue cheese, and sliced purple onion.