This cheesy ground beef and potato casserole has been my go-to comfort dish for chilly nights and hurried weeknights alike. I discovered this combination one evening when I wanted something that felt like a hug in a pan: tender diced russet potatoes baked with a savory seasoned beef and a rich, creamy mushroom sauce, all finished with two cups of sharp cheddar for a bubbly, golden top. The first time I served it, my partner went back for thirds, and our neighbor texted the next day asking for the recipe.

What makes this casserole special is its texture contrast — soft, almost buttery potatoes, slightly caramelized browned beef bits, and a sauce that binds everything together without being gluey. It’s forgiving, too: you can tweak the vegetables, swap the milk for a lighter option, and still get a satisfying outcome. I rely on it for potlucks because it scales easily, travels well, and the flavors seem to improve a day after baking when the sauce settles into the potatoes.

Ingredients

• Russet potatoes (2 pounds), peeled & diced: Choose firm, unblemished russets. Their high starch content breaks down during baking into a creamy interior while still holding shape. Peel for a smoother texture; dice into roughly 1/2- to 3/4-inch pieces for even cooking.
• Lean ground beef (1 pound): I prefer 90/10 or 93/7 to reduce excess fat. Browning develops flavor through the Maillard reaction — don’t overcrowd the pan. If using fattier meat, drain well after browning.
• Medium onion (1), chopped: Yellow or sweet onion provides savory sweetness; chop to similar size as the potatoes so they blend through the filling.
• Garlic (4 cloves), minced: Fresh garlic adds bright, aromatic lift. Add near the end of beef cooking to preserve its fragrance and avoid bitterness from burning.
• Frozen mixed vegetables (1 cup): A mix of carrots, peas, and corn adds color and fiber. Use thawed slightly or add straight to the pan for a quick sauté — frozen preserves convenience and reduces waste.
• Salt & pepper: Season throughout — a light hand on salt during assembly, and finish with a taste test after resting. If salt-sensitive, use low-sodium soup.
• Condensed cream of mushroom soup (10.5 oz can): The canned soup supplies body and umami. For a fresher version, substitute a homemade béchamel with mushrooms (see substitutions).
• Milk (1 cup; 2% recommended): Adds creaminess without being too heavy. Whole milk will be richer; skim will thin the sauce slightly.
• Sour cream (1/2 cup): Contributes tang and a silky mouthfeel. Full-fat sour cream yields the creamiest result.
• Worcestershire sauce (1 tablespoon): Anchors the savory profile with a subtle sweet-tangy depth.
• Italian seasoning (1 teaspoon): A blend of oregano, basil, and thyme for aromatic warmth. Use dried herbs sparingly to avoid overwhelming the mushroom flavor.
• Cheddar cheese (2 cups shredded, divided): Sharp cheddar adds tang and a great melt. Divide the cheese so half goes into the sauce and half finishes the top for that golden crust.

Instructions

Preheat and prep: Preheat the oven to 400°F and position the rack in the center. Grease a 9x13-inch casserole dish with butter or cooking spray so the potatoes won’t stick and the edges brown nicely. Uniform oven temperature ensures the top browns as the center finishes cooking. Layer the potatoes: Place the peeled and diced potatoes directly into the greased casserole dish in an even layer. Don’t parboil them — the casserole’s covered baking step (45 minutes) softens the potatoes thoroughly. Dice size is important: aim for 1/2" to 3/4" cubes for predictable cooking time. Brown the beef and onion: In a large skillet over medium-high heat, add the ground beef and chopped onion. Break the meat apart with a wooden spoon and cook until browned, about 8–10 minutes. Browning creates depth of flavor; if the pan becomes greasy, drain excess fat into a heat-safe container before proceeding. Finish the filling: Add the minced garlic and frozen mixed vegetables to the skillet and cook another 2–3 minutes, stirring often, until garlic is fragrant and vegetables are warmed. Season with salt and pepper, keeping in mind the canned soup and cheese will add more salt later. Transfer the mixture evenly over the potatoes. Make the sauce: In a medium bowl whisk together the condensed cream of mushroom soup, milk, sour cream, Worcestershire sauce, Italian seasoning, and 1 cup of shredded cheddar (half of the cheese). Whisk until smooth — the sour cream will make the sauce slightly tangy and silky. Pour the sauce over the beef and potatoes, then stir gently to distribute into an even layer. Bake covered: Cover the casserole tightly with aluminum foil and bake for 45 minutes. The cover traps steam so the potatoes cook through without drying out the top. If you assembled earlier and refrigerated, bake covered for 55–60 minutes. Finish with cheese: Remove the foil, sprinkle the remaining 1 cup of cheddar cheese evenly on top, and return to the oven uncovered for another 10–15 minutes, or until the cheese is melted and bubbly and a toothpick slides into a potato cube easily. For a deeper crust, broil 1–2 minutes while watching carefully. Rest and season: Let the casserole rest 5–10 minutes before serving to let the sauce set. Taste and add additional salt and pepper as needed. Resting will help portion cleanly and improve texture.

Storage Tips

Allow the casserole to cool to near room temperature, then cover tightly with plastic wrap or transfer to airtight containers. Refrigerate for up to 3 days. For freezing, portion into single-serve containers or wrap the entire cooled pan tightly with two layers of foil, then a layer of plastic wrap; freeze up to 3 months. To reheat refrigerated portions, microwave on medium power until warmed through or bake in a 350°F oven for 20–25 minutes. Frozen portions thaw overnight in the refrigerator before reheating; if baking from frozen, add 15–20 minutes to covered baking time and remove foil to brown the top for the last 10 minutes.

Ingredient Substitutions

If you prefer lower fat, swap the sour cream for plain Greek yogurt and use 1% milk. For a gluten-free option, use a certified gluten-free condensed cream of mushroom or substitute with a quick homemade mushroom sauce: sauté 8 ounces sliced mushrooms in 1 tablespoon butter, stir in 1 tablespoon flour, then whisk in 1 cup milk until thickened. Skip the ground beef for cooked shredded rotisserie chicken to create a milder, family-friendly version. For a vegetarian take, use a plant-based ground "meat" or a hearty mix of sautéed mushrooms and lentils; use vegetarian soup or béchamel instead of condensed soup.

Serving Suggestions

Serve generous scoops straight from the pan with a simple green salad dressed in lemon vinaigrette to cut the richness. For extra texture, top with chopped fresh parsley or chives. Pair with roasted Brussels sprouts or a steamed vegetable medley for color and brightness. This also works well alongside crusty bread to mop up the sauce, or spooned into bowls with a dollop of sour cream and a sprinkle of paprika for a cozy family-style dinner.

Cultural Background

This layered casserole reflects classic American home-cooking traditions that prioritize convenience and comfort. Mid-century cooks popularized casseroles as efficient one-dish meals — combining starch, protein, vegetables, and a creamy binder. The use of condensed soups became widespread in the 20th century because they shortened prep time and provided reliable texture. Today, casseroles retain that spirit of practicality while evolving through fresh ingredients and international flavor influences.

Seasonal Adaptations

In spring swap the frozen mix for fresh peas and diced asparagus; summer benefits from diced bell peppers and fresh corn kernels. In fall and winter, enhance warmth by adding 1/2 teaspoon smoked paprika or a pinch of nutmeg to the sauce, and replace mixed vegetables with roasted root vegetables like parsnip and rutabaga for hearty depth. For holiday crowds, double the recipe and bake in two pans to ensure even cooking and easier transport.

Meal Prep Tips

To make this ahead, assemble the casserole up to the point of baking and cover tightly; refrigerate for up to 24 hours. When ready to bake, allow an extra 10–15 minutes covered to account for the chilled interior. For efficient weeknight prep, brown the meat and chop potatoes while a morning errand is done, then finish the sauce and assemble before the kids arrive home. Portion into individual containers for quick lunches; reheat in the microwave or oven for a satisfying single-serve meal.

In short, this casserole is forgiving, crowd-pleasing, and adaptable — a reliable dish that rewards small techniques like even chopping, resting before serving, and finishing under the broiler for a golden top. Make it your own by swapping veggies, adjusting cheese, or seasoning to your family’s preference.