Wash and dry all produce. Bring a large pot of salted water to a boil. Pat chicken dry with a paper towel. Season all over with Tuscan heat spice, a large drizzle of olive oil, and salt and pepper.

Heat garlic herb butter in a large nonstick pan over medium-high heat. Add chicken and cook until golden brown, 5-6 minutes. Turn and continue to cook until golden brown and fully cooked through, 5-7 minutes more depending on the thickness of the chicken. (TIP: If the chicken is getting too dark, lower heat to medium.)

Meanwhile, peel, halve, and finely chop shallot and garlic. Roughly chop parsley. (TIP: It’s fine to use the stems—just finely chop.) When water is boiling, add spaghetti and cook until tender, 10-12 minutes. Reserve 1 cup pasta cooking water and drain. Make a slurry by whisking flour into cooking water; whisk until somewhat smooth. (TIP: A few clumps are okay.)

Transfer chicken to a plate and let rest. Do not wipe out pan; add shallot and garlic and cook over medium-high heat, stirring occasionally, until slightly softened, 30-60 seconds. Whisk in milk and slurry. Bring to a boil, then whisk in cream cheese and cook until smooth.

Meanwhile, dice chicken into bite-sized pieces and add to sauce in pan. Reserve 1/4 cup Parmesan for garnish and add rest to sauce. Season with salt and pepper. Stir well to coat chicken.

Add spaghetti to pan along with half the parsley. Using tongs, gently toss pasta and chicken until well coated. Divide into four serving bowls and sprinkle evenly with reserved Parmesan and remaining parsley.