Cook the pasta in a large pot of salted boiling water according to package instructions, usually 9-11 minutes. Reserve a cup of pasta water, then drain and set aside.

In a large skillet, heat olive oil over medium-high heat. Add diced chicken, season with salt and pepper, and sauté until golden brown, about 5-7 minutes. Transfer to a plate and keep warm.

Lower the heat and add minced garlic to the same skillet. Stir for about 1 minute until fragrant, being careful not to burn it.

Push the garlic to one side and add chopped sun-dried tomatoes and spinach. Stir and cook for 2-3 minutes, until spinach wilts and tomatoes warm through.

Pour in the heavy cream, stirring to combine. Bring to a simmer and add grated Parmesan cheese until melted and the sauce thickens, about 3-4 minutes.

Return the chicken to the skillet, add drained pasta, and toss gently to coat with the sauce. Use reserved pasta water if the sauce is too thick. Adjust seasoning with salt and pepper, then serve.