Butterfly or pound chicken breasts to an even ½-inch thickness — this is non-negotiable for even cooking. Uneven thickness means one end overcooks while the other is still raw.
Season both sides with salt. Dredge in flour, shaking off the excess. A thin coating browns beautifully.
Heat olive oil and butter in a large skillet over medium-high heat until foam subsides.
Cook chicken 3–4 minutes per side until golden brown and cooked through. Do not crowd the pan. Work in batches. Set aside.
Pour lemon juice and chicken broth into the same pan. Scrape up any browned bits — this is flavor.
Simmer 3 minutes until reduced by half. Add 2 more tbsp butter and swirl the pan until melted and emulsified.
Return chicken to the pan, spoon sauce over, and simmer 1 minute. Serve immediately.