Chicken Divan layers tender chicken and broccoli in a rich, cheesy cream sauce for a retro casserole that never goes out of style. This high protein, family-friendly chicken dish is comfort food at its finest.
Preheat oven to 375°F (190°C) and grease a 9x13-inch casserole dish.
Poach chicken breasts in simmering salted water for 10–12 minutes until just cooked through, then let rest 5 minutes and cut into bite-sized pieces.
Steam broccoli florets for 3–4 minutes until bright green and crisp-tender; immediately drain and spread in the bottom of the dish.
Layer chicken evenly over the broccoli, then in a mixing bowl, combine sour cream, mayonnaise, cream of chicken soup, lemon juice, Dijon mustard, garlic powder, salt, black pepper, and 1 cup shredded cheddar cheese; mix well.
Spread the sauce mixture over chicken and broccoli, then top with the remaining 0.5 cup cheese. In a separate bowl, toss panko breadcrumbs with melted butter and sprinkle evenly on top.
Bake casserole uncovered for 25–30 minutes or until bubbling at the edges and golden brown on top. Let cool 10 minutes before serving to set the layers.