Bring a large pot of salted water to a boil. Add rotini and cook until al dente, about 8–10 minutes. Reserve 1/2 cup pasta water, then drain and set aside.

Season chicken with garlic powder, smoked paprika, salt, and pepper. Toss to coat evenly.

Heat 1 tbsp olive oil and 2 tbsp butter in a large skillet over medium-high. When butter foams, add chicken. Sear until edges turn golden and pieces register 165°F, about 5–7 minutes. Remove chicken and set aside.

Reduce heat to medium. In the same skillet, melt 3 tbsp butter and add minced garlic. Sauté until fragrant, about 30 seconds; do not let it burn.

Pour in chicken broth and heavy cream, stirring to combine. Simmer gently until the mixture warms and starts to thicken.

Add Velveeta cubes, stirring constantly until the sauce becomes smooth and glossy. Stir in grated Parmesan and Italian seasoning. Adjust salt and pepper to taste.

Add cooked rotini to the skillet and toss to coat. If the sauce seems too thick, add reserved pasta water a splash at a time until it reaches a silky consistency.

Return the chicken to the skillet and stir gently to combine. Heat through for a minute. The chicken should look glossy and the sauce should cling to each rotini spiral.

Plate hot and garnish with chopped fresh parsley and extra Parmesan. Serve right away.