Prep the chicken: Pat dry. Season both sides with 1/2 teaspoon salt, pepper, garlic powder, and Italian seasoning.
Sear: Heat olive oil in a large skillet over medium-high.
Add chicken and cook 4–5 minutes per side until golden and just cooked through. Transfer to a plate and tent with foil.
Sauté aromatics: Lower heat to medium. Add garlic and sun-dried tomatoes.
Cook 30–60 seconds, stirring, until fragrant. Do not burn the garlic.
Deglaze: Pour in chicken broth. Scrape up browned bits.
Simmer 2 minutes to reduce slightly.
Make it creamy: Reduce heat to low. Whisk together Greek yogurt and half-and-half in a small bowl to temper. Slowly stir this mixture into the pan.
Add Parmesan and red pepper flakes. Stir until smooth.
Finish the sauce: Add lemon juice and remaining 1/2 teaspoon salt, adjusting to taste. The sauce should be creamy and gently simmering, not boiling.
Return chicken to pan: Nestle chicken into the sauce and spoon sauce over the top.
Simmer 2–3 minutes to warm through and thicken slightly.
Garnish and serve: Top with chopped basil or parsley. Serve over whole-grain pasta, mashed or roasted potatoes, zucchini noodles, or rice.