Cook the bacon in a large skillet until crisp. Transfer to a paper towel-lined plate and chop when cool. Reserve about 1–2 tablespoons of the bacon drippings in the skillet; discard excess.

Slice the chicken breasts into 1/2-inch strips. Season with salt, pepper, onion powder, and Italian seasoning.

Increase heat to medium-high and sear the chicken in the bacon drippings until golden and cooked through, about 4–5 minutes per side depending on thickness. Remove the chicken and set aside.

Meanwhile, bring a large pot of salted water to a boil. Cook the rotini until al dente (usually 1–2 minutes less than package directions). Drain and set aside.

In the same skillet over medium heat, melt the butter. Add the minced garlic and sauté 30–45 seconds until fragrant.

Sprinkle in the flour and whisk to form a roux; cook 1 minute to remove the raw flour taste.

Gradually whisk in the half-and-half until smooth and slightly thickened, about 2–3 minutes. Stir in the ranch seasoning.

Reduce heat to low and add the shredded cheddar a handful at a time, stirring until melted and the sauce is smooth. If the sauce is too thick, add a splash of milk to loosen.

Return the chicken to the skillet, then add the drained pasta. Toss gently until everything is coated and heated through.

Sprinkle chopped bacon on top and serve warm.