Bring a large pot of salted water to a boil. Cook pasta per package instructions, about 8-10 minutes. Reserve ½ cup pasta water before draining.

Slice chicken breasts lengthwise into cutlets and season with garlic powder, salt, and pepper.

In a skillet, heat olive oil and butter over medium-high heat. Sear chicken cutlets for about 5-6 minutes each side until golden and cooked through. Remove and slice.

In the same skillet, lower heat, sprinkle in flour to create a roux, then whisk in chicken broth, heavy cream, pesto, lemon juice, and sun-dried tomatoes. Simmer for 3-5 minutes until thickened.

Stir in spinach and cook an additional 2-3 minutes until wilted.

Add drained pasta to the skillet and toss to combine. Use reserved pasta water to adjust sauce consistency as needed.

Mix sliced chicken back into the skillet, combine well, and serve with grated Parmesan cheese if desired.