Baked Potato Chicken Broccoli Casserole

The first time I made this casserole, my kitchen smelled like something straight out of a grandmother's Sunday kitchen. My roommate wandered in, following the scent of bubbling cheese and thyme, and asked what special occasion I was cooking for. I told her it was just Tuesday dinner, but honestly, this hearty bake does make any night feel like a celebration.

Last winter, I brought this to a friend's potluck right after she'd had her second baby. Between the exhaustion and the chaos of a newborn, nobody had energy to cook. Within an hour of arriving, that casserole pan was completely empty. Her husband kept asking me for the recipe, writing it down on the back of a diaper box while trying to bounce a fussy infant.

Ingredients

• 2 cups cooked chicken breast: Rotisserie chicken works perfectly here, or use leftover roasted chicken from earlier in the week
• 4 medium russet potatoes: Dice them evenly so they all cook through at the same rate
• 2 cups broccoli florets: Fresh is best, but frozen works in a pinch, just thaw and pat dry
• 1 small onion, finely chopped: Red onion adds a nice sweetness, but yellow works too
• 2 cloves garlic, minced: Fresh garlic makes all the difference, don't skip it
• 1 cup sour cream: Full fat gives the best texture, but Greek yogurt is a decent swap
• 1 cup shredded cheddar cheese plus ½ cup more: Sharp cheddar has more flavor so you can use less
• ½ cup milk: Whole milk creates the creamiest sauce
• 2 tablespoons unsalted butter: Melt it before mixing so it incorporates evenly
• 1 teaspoon salt: Adjust based on whether your chicken was pre seasoned
• ½ teaspoon black pepper: Freshly cracked has way more flavor
• ½ teaspoon paprika: Smoked paprika adds a subtle depth regular paprika lacks
• ½ teaspoon dried thyme: Fresh thyme is lovely but dried works perfectly fine here

Instructions

Get everything ready first:

Preheat your oven to 400°F and grease a 9x13 baking dish with butter or cooking spray

Prep the potatoes:

Boil the diced potatoes for 8 to 10 minutes until just fork tender, then drain them well

Steam the broccoli:

Cook broccoli florets for 3 to 4 minutes until bright green and slightly tender

Combine everything:

Mix the cooked potatoes, broccoli, chicken, onion and garlic in a large bowl

Make the creamy sauce:

Whisk together sour cream, milk, melted butter, 1 cup cheese and all seasonings until smooth

Coat the mixture:

Pour the sauce over the potato chicken mixture and stir gently to coat everything evenly

Assemble the casserole:

Transfer everything to the baking dish and sprinkle with the remaining ½ cup cheese

Bake until golden:

Bake uncovered for 25 to 30 minutes until bubbly and golden on top

Let it rest:

Wait 5 minutes before serving so the sauce sets slightly and makes serving easier

Save

My niece turned her nose up at broccoli for years until this casserole entered the rotation. Something about the cheese sauce and tender potatoes made her forget she was eating vegetables. Now she actually requests this for her birthday dinner, which still feels like a small parenting victory every single time.

Make It Your Own

Sometimes I add cooked bacon bits or swap in Monterey Jack cheese for a milder flavor. The recipe is incredibly forgiving, which is probably why it's become my go to when I need to feed a crowd without spending hours in the kitchen.

The Perfect Texture

I've learned that cutting potatoes into even sized cubes prevents some from turning to mush while others stay undercooked. Also, letting the casserole rest for those five minutes seems simple, but it's the difference between a neat scoop and a messy slide onto the plate.

Serving Suggestions

A crisp green salad with vinaigrette cuts through all that rich creaminess perfectly. If you're serving a crowd, crusty bread on the side never hurts either.

• Warm the plates briefly in the oven before serving
• Keep extra hot sauce on the table for heat lovers
• Pair with a light white wine like Pinot Grigio

Save

There's something deeply satisfying about a casserole that tastes like it took hours but really just requires some prep work and a hot oven. This one has earned its permanent spot in my regular rotation.

Recipe FAQs

→ Can I make this casserole ahead of time?

Yes, assemble the entire casserole up to 24 hours in advance and refrigerate. Add 10-15 minutes to the baking time if baking cold from the refrigerator.

→ Can I use raw chicken instead of cooked?

You'll need to cook the chicken first. Cube raw chicken breast and sauté until cooked through, or use poached/rotisserie chicken for convenience.

→ What other vegetables work well in this dish?

Cauliflower, carrots, or green beans make excellent additions or substitutions. Adjust cooking times so vegetables aren't overcooked.

→ How do I store leftovers?

Store in an airtight container in the refrigerator for 3-4 days. Reheat individual portions in the microwave or cover with foil and warm in a 350°F oven.

→ Can I freeze this casserole?

Yes, freeze before baking for up to 3 months. Thaw overnight in the refrigerator, then bake as directed. Already-baked portions can be frozen for 2 months.

→ What can I substitute for sour cream?

Greek yogurt provides a lighter tangy alternative. Plain Greek yogurt with similar fat content works best to maintain the creamy texture.