In a large pot, bring water to a boil and cook pasta according to package directions.
Season the chicken with salt and pepper.
Heat olive oil in a large skillet over medium-high heat. Once heated, add the chicken and cook until just cooked through, about 4-6 minutes.
Transfer the cooked chicken to a plate and set aside.
Lower the heat to medium heat. In the same skillet, add the butter. When most of the butter has melted, add the onions and sun-dried tomatoes. Cook for about 3 minutes, allowing the onions and sun-dried tomatoes to soften.
Add the garlic and cook for 1 minute, just until the garlic is fragrant and soft.
Add the tomato paste, oregano, paprika, salt, and pepper. Stir to combine.
Slowly pour in the heavy cream and milk, stirring to combine.
Add the spinach and parmesan cheese; stir.
Reduce the heat to low, then return the cubed chicken to the skillet and add the pasta. Stir and cook for about 1-2 minutes to allow the chicken to soak up the sauce flavors. Serve immediately, garnished with sliced basil leaves.
Notes
Makes approximately 4 servings (2 ounces of pasta per serving).Storage: allow the pasta to cool, then store in an airtight container in the refrigerator for up to 4-5 days.