Boil a large pot of salted water and cook pasta until al dente.
Cut chicken into bite-sized pieces, season with salt and pepper, then lightly coat with flour.
Heat butter and olive oil in a skillet over medium-high heat. Cook chicken until lightly golden and no longer pink. Remove and set aside.
Remove pan from heat. Add garlic, chicken broth, lemon juice, Dijon mustard, and Italian seasoning. Return to heat and simmer briefly, scraping up browned bits.
Add chicken, cream, and spinach. Cook for about 5 minutes until chicken is fully cooked and sauce thickens.
Drain pasta and combine with sauce. Stir in parmesan cheese. Adjust seasoning and serve warm.