Heat the olive oil in a large skillet over medium-high heat.
Add the chicken pieces to the skillet and season with garlic powder, smoked paprika, salt, and black pepper.
Cook the chicken, stirring occasionally, until browned and cooked through, about 6-8 minutes.
Add the minced garlic to the skillet and cook for 1 minute until fragrant.
Pour in the buffalo wing sauce and ranch dressing, stirring to combine with the chicken.
Add the chicken broth and uncooked penne pasta to the skillet. Stir well to combine.
Bring the mixture to a boil, then reduce the heat to medium-low.
Cover and simmer for 12-15 minutes, stirring occasionally, until the pasta is tender and most of the liquid is absorbed.
Sprinkle the shredded cheddar and mozzarella cheeses evenly over the pasta and chicken.
Cover the skillet and cook for an additional 2-3 minutes, until the cheese is melted and bubbly.
Remove from heat and garnish with sliced green onions and chopped fresh parsley.
Serve immediately, enjoying the bold, zesty flavors of the buffalo ranch chicken pasta skillet.