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Onion Casserole
Onion Casserole is a vintage comfort dish that celebrates the natural sweetness of onions in a creamy, cheesy bake. Popular during the mid-20th century when casseroles were a staple in American kitchens, this recipe layers cooked onions with cracker meal, cheese, and herbs, then bakes them in milk for a hearty side dish. Its rustic simplicity and savory depth make it a beloved addition to family dinners, potlucks, and holiday spreads. The toasted top and tender onion base deliver warmth and nostalgia in every bite, embodying the homestyle charm of classic casserole cooking.
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Prep Time 20 minutes
Cook Time 40 minutes
Total Time 1 hour
Course Side Dish
Cuisine American
Servings 6
Calories 220 kcal

Ingredients
  

  • 6 onions (medium, cooked until tender)
  • 1 cup cracker meal (or finely crushed saltine crackers)
  • 1 cup cheese (grated, cheddar recommended)
  • ¼ tsp sweet basil
  • 1 tbsp parsley flakes
  • 2 cups milk

Instructions
 

Step 1: Cook Onions

  • Peel and boil onions in salted water until tender. Drain well.

Step 2: Layer Ingredients

  • In a greased casserole dish, place cooked onions.
  • Cover alternately with cracker meal and grated cheese.
  • Sprinkle with a pinch of sweet basil.

Step 3: Add Toppings

  • Top with parsley flakes.

Step 4: Add Milk and Bake

  • Pour milk over casserole, covering about 4/5 of the way.
  • Bake uncovered at 350°F (175°C) for 35–40 minutes until golden and bubbly.

Tips

  • Use sweet onions (Vidalia/Walla Walla) for milder flavor; yellow onions for stronger flavor
  • Parboil onions briefly, then slice or quarter before layering
  • Substitute breadcrumbs for cracker meal if unavailable
  • Add a small amount of black pepper or paprika for gentle heat and color
  • Swap milk with half-and-half for a richer casserole
  • Use a blend of cheeses (Cheddar, Swiss, or Monterey Jack) for added flavor
  • Add a small amount of garlic powder if desired (not traditional but tasty)
  • Make it a full meal by adding cooked potatoes or mushrooms
  • For crisper topping, uncover for the last 5–10 minutes of baking

Nutrition

Calories: 220kcalCarbohydrates: 20gProtein: 9gFat: 12gSaturated Fat: 6gPolyunsaturated Fat: 1gMonounsaturated Fat: 3gCholesterol: 25mgSodium: 320mgPotassium: 250mgFiber: 2gSugar: 6gVitamin A: 300IUVitamin C: 10mgCalcium: 180mgIron: 1mg
Keyword baked onions, cheese casserole, comfort food, easy casserole, old-fashioned recipe, onion casserole, vintage recipe
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