Homestyle Potato and Onion Casserole

By AislePrompt Editorial · ·

How this recipe was made — this recipe was drafted by AislePrompt's AI-assisted pipeline from technique templates and USDA-sourced nutrition data, and published by AislePrompt Editorial — see how AislePrompt recipes are developed and reviewed.

A creamy, comforting casserole featuring tender potatoes and caramelized onions baked until golden, ideal for weeknight dinners. This American-inspired one-pot recipe, ready in about 60 minutes, pairs russet potatoes, yellow onions, butter for a weeknight-friendly dinner that comes together with one pan and minimal cleanup. Each serving lands at about 420 calories and feeds 6, so it slots cleanly into a weekly meal plan and pairs well with a quick salad or grain on the side. Tap "Plan a meal with the AI" below to drop this recipe into your week and send the ingredients straight to Instacart. Nutrition values are approximate, calculated from USDA FoodData Central (fdc.nal.usda.gov) — verify against ingredient labels for any health-driven dietary plan.

Prep: 25 min Cook: 35 min Serves 6 American cuisine 420 cal/serving
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Ingredients

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Instructions

  1. Step 1: Preheat oven to 375°F. Grease a 9x13-inch baking dish with 1 tablespoon butter.
  2. Step 2: In a large pot, bring 4 quarts of water with 1 tablespoon salt to a boil. Add 2 pounds diced potatoes and cook for 10 minutes until slightly tender. Drain and set aside.
  3. Step 3: Melt 2 tablespoons butter in a large skillet over medium heat. Add 2 medium chopped onions and cook for 5 minutes until golden brown, stirring occasionally.
  4. Step 4: In a medium bowl, whisk together 1 cup heavy cream, 1/2 cup whole milk, 1/2 teaspoon salt, 1/2 teaspoon black pepper, and 1 teaspoon dried thyme.
  5. Step 5: In the baking dish, layer half of the cooked potatoes, then half of the onions, then the remaining potatoes and onions. Pour the cream mixture evenly over the top.
  6. Step 6: Sprinkle 1 cup grated cheddar cheese evenly over the surface.
  7. Step 7: Bake for 30-35 minutes until the cheese is melted and bubbly and edges are golden, then let rest for 10 minutes before serving.

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