In a medium bowl, toss the chicken pieces with 1 tbsp olive oil, Italian seasoning, garlic powder, salt, and black pepper until evenly coated.

Heat a large skillet over medium-high heat. Add the seasoned chicken and cook for 5-7 minutes, stirring occasionally, until browned and cooked through. Remove chicken from the skillet and set aside.

While the chicken cooks, bring a large pot of salted water to a boil. Add the pasta and cook according to package directions until al dente. Drain, reserving 1/2 cup of pasta water, and toss with 1 tbsp olive oil to prevent sticking. Set aside.

In the same skillet (no need to clean), melt the butter over medium heat. Add the minced shallot and cook for 2-3 minutes until softened. Add the minced garlic and red pepper flakes (if using), and cook for another minute until fragrant.

Stir in the sliced sun-dried tomatoes. Pour in the chicken broth and bring to a simmer, scraping up any browned bits from the bottom of the skillet. Reduce the heat to medium-low.

Stir in the heavy cream and grated Parmesan cheese. Simmer for 5-7 minutes, stirring occasionally, until the sauce thickens slightly.

Stir in the fresh spinach a handful at a time, allowing it to wilt before adding more. Once all spinach is wilted, return the cooked chicken to the skillet. Season the sauce with salt and black pepper to taste.

Add the drained pasta to the skillet with the sauce and chicken. Toss to combine thoroughly. If the sauce seems too thick, add a splash or two of the reserved pasta water until it reaches your desired consistency.

Serve immediately, garnished with extra grated Parmesan cheese and fresh basil, if desired.