Oo-la-la Onion Casserole

Tam D


This simple yet elegant dish will fill your home with its tantalizing aroma! It's fantastically rich and delicious, and could easily be served as a main dish or as a side or course in a special occasion meal. It's as decadent as any upper crust restaurant -- you will not be disappointed!


★★★★★ 1 vote

40 Min
45 Min


  • 3 Tbsp
  • 3 large
    sweet onions, sliced thin
  • 2 c
    shredded swiss cheese
  • 10 oz
    can cream of mushroom soup
  • 2/3 c
    whole milk or rich milk substitute
  • 1 tsp
    soy sauce
  • 2 tsp
    beef base, or good quality bouillon cubes
  • 1/4 tsp
    white pepper
  • 8 slice
    french-style bread, cut 1/2-3/4"

How to Make Oo-la-la Onion Casserole


  1. In a large 3 qt. saucepan, saute' onion slices in melted butter over med-low heat, until they're golden yellow, but not browned.
    Note: This step takes time -- 20-30 min. Stir the onion often. Watch carefully the last few minutes to prevent scorching.
  2. Meanwhile, with food release spray, prepare 4-8 single-serving baking dishes (such as oven-safe soup bowls, ramekins, oval casserole or au gratin dishes); use four for meal-size servings, or eight dishes for appetizer and sides.
  3. In a small saucepan, stir together the soup, beef base, milk, soy sauce, and pepper until warm and blended. Turn off heat and let set until onions are ready.
  4. Divide the onions evenly into your baking dishes.
  5. Layer 2/3 of the shredded Swiss cheese over the cooked onion.
  6. Pour the soup mixture over the cheese layer, and stir gently to combine.
  7. Cover the tops with a slice/s of french-style bread.
  8. Bake, uncovered, at 350* for 10-15 min, til heated through.
  9. Remove from oven. Push bread slices into the onion and soup mixture. Top with remaining cheese, and return to oven for an additional 10-15 min, or until lightly browned and bubbly.
  10. Turn off the oven and allow the casserole to rest in the oven for 10-15 min more.
    Remove from oven and serve immediately, with a light green salad, and a glass of favorite wine.
  11. NOTE: 1) My family is gluten intolerant so I used slices of GF french-style bread, which worked perfectly.
    2) You could bake this in a 3 qt. casserole dish, but it's not as pretty when you serve it. If you're going to use the large casserole dish I recommend breaking the bread into chunks, to make serving easier.

Printable Recipe Card

About Oo-la-la Onion Casserole

Main Ingredient: Vegetable
Regional Style: French
Dietary Needs: Vegetarian
Other Tag: Quick & Easy

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