Leftover Ham and Potato Cheesy Casserole – Cozy, Easy, and Crowd-Pleasing
If you’ve got leftover ham in the fridge and a couple of potatoes on the counter, this casserole is the perfect way to turn them into a comfort-filled dinner. It’s creamy, cheesy, and loaded with hearty flavor that feels like a warm hug. The best part?
It’s simple to throw together with everyday ingredients. Whether you’re feeding family after a holiday or just craving something satisfying, this recipe checks all the boxes. It reheats beautifully and makes fantastic leftovers, too.
Leftover Ham and Potato Cheesy Casserole - Cozy, Easy, and Crowd-Pleasing
Ingredients
Method
- Preheat and prep. Heat the oven to 375°F (190°C). Grease a 9x13-inch baking dish with butter or oil. If your oven runs cool, go to 400°F for a crisper top.
- Slice the potatoes and onion. Aim for 1/8-inch potato slices so they cook evenly.A mandoline helps, but a sharp knife works fine.
- Make the cheese sauce base. In a saucepan, melt 4 tablespoons butter over medium heat. Stir in the flour and cook 1–2 minutes, whisking, until it smells nutty but not browned.
- Add liquids. Slowly whisk in the milk and broth. Keep whisking until smooth and slightly thickened, 3–5 minutes.
- Season and enrich. Stir in garlic, Dijon, smoked paprika, black pepper, and a small pinch of salt.Simmer 1 minute. Off the heat, stir in sour cream (if using), 1 1/2 cups cheddar, and 1/4 cup Parmesan until melted.
- Layer the casserole. Add half the potatoes to the dish in an even layer. Top with half the onions and half the diced ham.Spoon over half the cheese sauce. Repeat with remaining potatoes, onions, ham, and sauce.
- Finish with cheese. Sprinkle the remaining 1/2 cup cheddar and 1/4 cup Parmesan over the top. Add a pinch of thyme or parsley if you like.
- Bake covered, then uncovered. Cover tightly with foil and bake 35–40 minutes.Remove foil and bake another 20–25 minutes, until bubbly and the potatoes are tender when pierced with a knife.
- Rest before serving. Let it sit 10–15 minutes so it sets and slices cleanly. Garnish with more herbs if you want a fresh pop.
What Makes This Special
This casserole hits that ideal balance of creamy and cheesy without being heavy or fussy.
The ham brings a savory, smoky punch, while the potatoes bake up tender and silky under a rich sauce. You don’t need fancy tools or techniques—just a baking dish and a little patience while the oven does the work. It’s also versatile: swap cheeses, add veggies, or use different potatoes based on what you have.
Most importantly, it’s reliable, comforting, and budget-friendly.
What You’ll Need
- Leftover cooked ham, diced (about 2 cups)
- Russet or Yukon Gold potatoes, thinly sliced (about 2 pounds)
- Yellow onion, thinly sliced (1 medium)
- Garlic, minced (2–3 cloves)
- Butter (4 tablespoons)
- All-purpose flour (3 tablespoons)
- Milk (2 cups; whole milk preferred for creaminess)
- Chicken or vegetable broth (1/2 cup)
- Sharp cheddar cheese, shredded (2 cups)
- Parmesan, grated (1/2 cup)
- Sour cream (1/2 cup; optional but adds richness)
- Dijon mustard (1 teaspoon; for depth)
- Smoked paprika (1/2 teaspoon)
- Black pepper (to taste)
- Salt (go light—ham and cheese are salty)
- Fresh thyme or parsley, chopped (1–2 tablespoons, optional)
- Olive oil or butter for greasing the dish
How to Make It
- Preheat and prep. Heat the oven to 375°F (190°C). Grease a 9×13-inch baking dish with butter or oil. If your oven runs cool, go to 400°F for a crisper top.
- Slice the potatoes and onion. Aim for 1/8-inch potato slices so they cook evenly.
A mandoline helps, but a sharp knife works fine.
- Make the cheese sauce base. In a saucepan, melt 4 tablespoons butter over medium heat. Stir in the flour and cook 1–2 minutes, whisking, until it smells nutty but not browned.
- Add liquids. Slowly whisk in the milk and broth. Keep whisking until smooth and slightly thickened, 3–5 minutes.
- Season and enrich. Stir in garlic, Dijon, smoked paprika, black pepper, and a small pinch of salt.
Simmer 1 minute. Off the heat, stir in sour cream (if using), 1 1/2 cups cheddar, and 1/4 cup Parmesan until melted.
- Layer the casserole. Add half the potatoes to the dish in an even layer. Top with half the onions and half the diced ham.
Spoon over half the cheese sauce. Repeat with remaining potatoes, onions, ham, and sauce.
- Finish with cheese. Sprinkle the remaining 1/2 cup cheddar and 1/4 cup Parmesan over the top. Add a pinch of thyme or parsley if you like.
- Bake covered, then uncovered. Cover tightly with foil and bake 35–40 minutes.
Remove foil and bake another 20–25 minutes, until bubbly and the potatoes are tender when pierced with a knife.
- Rest before serving. Let it sit 10–15 minutes so it sets and slices cleanly. Garnish with more herbs if you want a fresh pop.
How to Store
- Refrigerate: Cool fully, then cover and refrigerate for up to 4 days.
- Freeze: Portion into airtight containers and freeze for up to 2 months. Thaw overnight in the fridge before reheating.
- Reheat: Warm in a 350°F oven, covered, for 20–25 minutes, or microwave in short bursts.
Add a splash of milk if it seems dry.
Benefits of This Recipe
- Great use of leftovers: Ham shines here, and it stretches into a full meal.
- Family-friendly flavors: Creamy sauce and melty cheese win over picky eaters.
- Flexible ingredients: Works with different cheeses, potatoes, and add-ins.
- Make-ahead friendly: Assemble a day ahead and bake when needed.
- Budget-conscious: Pantry staples keep costs down without skimping on comfort.
What Not to Do
- Don’t oversalt the sauce. Ham and cheese already bring salt. Taste as you go.
- Don’t skip the foil stage. Covered baking helps the potatoes cook through before the top browns.
- Don’t slice potatoes too thick. Thick slices take longer and may stay firm in the center.
- Don’t use pre-shredded cheese if you can avoid it. It contains anti-caking agents that can make the sauce grainy.
- Don’t rush the rest time. A short rest helps the sauce settle for cleaner slices and better texture.
Variations You Can Try
- Broccoli cheddar: Fold in lightly steamed broccoli florets for a veggie boost.
- Gruyère and leek: Swap cheddar for Gruyère and use sautéed leeks instead of onion for a French twist.
- Jalapeño kick: Add chopped pickled jalapeños and a dash of hot sauce to the cheese sauce.
- Ranch-style: Stir in 1–2 teaspoons ranch seasoning and top with green onions and crumbled bacon.
- Sweet potato blend: Use half russet and half sweet potatoes for sweet-savory contrast.
- Gluten-free: Use a gluten-free all-purpose flour or cornstarch slurry to thicken the sauce.
- Lighter version: Use 2% milk, reduce cheese by 1/2 cup, and skip sour cream. It will still be creamy.
FAQ
Do I need to parboil the potatoes?
No.
Thinly sliced potatoes will cook through during the covered bake. If your slices are thicker, add 10–15 minutes covered or parboil for 5 minutes first.
Can I use pre-cooked scalloped potatoes or boxed potatoes?
You can, but reduce the sauce quantity slightly and watch the salt. Boxed potatoes cook faster, so start checking early.
What’s the best cheese for melting?
Sharp cheddar gives classic flavor and melts well.
Monterey Jack, Gruyère, or a cheddar-Mozzarella mix also work. Avoid very aged, dry cheeses on their own.
Can I add vegetables?
Absolutely. Peas, corn, broccoli, spinach, or sautéed mushrooms fit right in.
Pat watery veggies dry or sauté first so the sauce stays thick.
How do I keep the sauce from curdling?
Keep heat moderate, add dairy off the heat, and avoid boiling once the cheese is in. Whisk steadily and melt gently for a silky sauce.
What if I only have half-and-half or cream?
Use it and thin with a little broth or water. The sauce will be richer, so consider cutting back a bit on cheese or sour cream.
Can I assemble this ahead?
Yes.
Assemble up to 24 hours in advance, cover tightly, and refrigerate. Add 5–10 minutes to the covered bake time if going straight from the fridge.
Why is my casserole watery?
Likely from high-moisture veggies or under-thickened sauce. Sauté watery add-ins first, and cook the roux long enough to thicken.
Let the casserole rest to set.
How do I get a crispier top?
Broil for 1–2 minutes at the end, or sprinkle a mix of breadcrumbs and Parmesan before the final bake. Watch closely so it doesn’t burn.
What can I use instead of ham?
Cooked bacon, sausage, rotisserie chicken, or turkey work well. For a meatless version, add extra veggies and bump up the cheese slightly.
Wrapping Up
Leftover Ham and Potato Cheesy Casserole is the kind of recipe that makes weeknights easier and leftovers exciting.
It’s flexible, forgiving, and full of comfort, with simple ingredients that deliver big flavor. Keep this one in your back pocket for post-holiday meals or anytime you want a cozy bake that feeds a crowd. Serve it with a crisp salad or roasted veggies, and you’re set for a no-stress, satisfying dinner.
