Pound chicken breasts to even thickness using a meat mallet. Season both sides generously with Italian seasoning, garlic powder, onion powder, salt, and pepper.
Heat olive oil in a large skillet over medium-high heat until shimmering. Add chicken and cook undisturbed for 5-6 minutes per side until golden brown and internal temperature reaches 165°F. Transfer to a plate and tent with foil.
In the same skillet, melt 1 tablespoon butter over medium heat. Add minced garlic and cook for 30 seconds until fragrant. Whisk in flour and cook for 1 minute.
Gradually whisk in chicken broth and lemon juice, scraping up browned bits from the pan. Bring to a simmer and cook for 2-3 minutes until slightly thickened. Stir in lemon zest and remaining butter until melted.
Return chicken to the skillet, spooning sauce over each piece. Simmer gently for 2 minutes. Remove from heat and fold in fresh basil. Serve immediately with pan sauce drizzled over top.
