Season the chicken breasts with Italian seasoning, crushed red pepper, salt, and pepper.
Heat olive oil in a large skillet over medium heat. Add chicken and cook for 5–6 minutes per side until golden and cooked through. Remove and set aside.
In the same skillet, add 1 tablespoon butter, onion, and asparagus. Cook for 2–3 minutes until slightly tender.
Add garlic and cook for about 1 minute until fragrant.
Pour in heavy cream and lemon juice, then stir in Parmesan cheese. Mix well to create a smooth sauce.
Return chicken to the skillet and simmer for 3–4 minutes until the sauce thickens.
Taste and adjust seasoning if needed. For a thinner sauce, add a splash of water or chicken broth.
This Creamy Lemon Chicken with Asparagus is now ready to serve.