Cook the penne pasta according to package instructions until al dente.
While the pasta cooks, heat olive oil in a large skillet over medium heat and sauté the chopped onion and minced garlic until softened.
Add the shredded chicken and ranch seasoning to the skillet, stirring to combine.
Stir in the cream cheese until it melts and blends with the chicken and seasoning.
Pour in the chicken broth and mix well to adjust the sauce's consistency.
Add the cooked penne pasta to the skillet, tossing to coat it in the creamy mixture.
Mix in the shredded cheddar cheese until melted and fully incorporated.
Season with salt and pepper to taste, then serve immediately.
