Mary'S Onion Casserole

Prep: 10 min Cook: 60 min Serves: 4 Cuisine: American

A comforting onion casserole featuring tender sliced onions layered with butter and seasoned simply, perfect for family dinners and hearty gatherings.

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Ingredients

  • 8 large yellow onions
  • 3 Tbsp butter
  • salt

Instructions

  1. Put a layer of sliced onions in the bottom of a casserole dish.
  2. Sprinkle with salt and pepper.
  3. Add 8 small nobs of butter around each layer of onions.
  4. Repeat the layering process until the casserole is full.
  5. Cover and bake at 350°F (175°C) for 1 hour without removing the cover.

Tips & Substitutions

For a deeper flavor, consider caramelizing the onions before layering them in the casserole. You can substitute yellow onions with sweet onions for a milder taste. Adding some herbs like thyme or rosemary can enhance the dish. If you want a creamier texture, consider mixing in a bit of sour cream or cream cheese between the layers.

Serving Suggestions

This onion casserole pairs beautifully with grilled meats or roasted vegetables, making it a versatile side dish for family dinners. You can serve it alongside a fresh salad or with crusty bread for a comforting meal. For a complete vegetarian experience, consider serving with a side of Cauliflower Cajun Style.

Storage & Reheating

Store any leftovers in an airtight container in the refrigerator for up to 3 days. To reheat, place the casserole in the oven at 350°F (175°C) until warmed through, about 20-30 minutes. You can also microwave individual portions, but the oven method helps retain the texture better.

Nutrition & Diet Analysis (per serving)

Each serving of Mary'S Onion Casserole contains roughly 347 calories, with 2g protein, 16g carbohydrates, and 33g fat. It is a good source of dietary fiber (12% of the Daily Value). Note that it is relatively high in sodium, at 508mg per serving (22% of the Daily Value).

347 kcal 17% DV
Protein Fat Carbs

Macronutrients

Protein 1.9g 4% DV
Total Fat 32.9g 42% DV
Carbs 15.7g 6% DV
Fiber 3.4g 12% DV
Sugar 0g

Electrolytes

Sodium 508.5mg 22% DV
Potassium 266.1mg 6% DV
Cholesterol 33.8mg 11% DV

Vitamins & Minerals

Vitamin C 3.6mg 4% DV
Calcium 40.3mg 3% DV
Iron 0.5mg 3% DV
Diet fit Low-carb Under 400 cal
Contains Milk

Estimated from ingredients & per-serving nutrition — verify against package labels for allergies or strict diets.

* % Daily Values based on a 2,000 calorie diet (FDA 2020).

Frequently Asked Questions

Can I use different types of onions for this recipe?

Yes, you can experiment with different onion varieties! Sweet onions will give a milder flavor, while red onions can add a colorful twist. Just keep in mind that different onions may affect the overall sweetness and texture of the dish.

What can I do if I find the casserole too salty?

If the casserole turns out too salty, you can balance it by adding a bit more butter or even a splash of cream. You could also serve it with a side of plain rice or bread to help absorb the saltiness.

Is this casserole suitable for freezing?

Yes, you can freeze this onion casserole! Just make sure it has cooled completely before transferring it to a freezer-safe container. It can be stored for up to 2-3 months. To reheat, thaw it in the fridge overnight and bake as directed.

Nutrition is estimated from USDA FoodData Central ingredient data and may vary with brand, portion and preparation — see our methodology. This information is for general educational purposes only and is not medical or dietary advice (disclaimer).

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