Source: https://ohioeggs.com/recipes/savory-french-onion-casserole/

Savory French Onion Casserole

grocery Prep: 25min

timer Cook: 75min

restaurant 10-12 servings

3 tbsp of unsalted butter

2 – 2.5 pounds yellow onions, thinly sliced

1 tsp salt

1 bay leaf

1 tsp dried thyme

½ cup white wine (we recommend Sauvignon Blanc)

1 large loaf of sourdough bread cut into 1-inch cubes (best results from toasted or allowing cubes to dry overnight)

6 large eggs

1 cup heavy cream

2 1/2 cups whole milk

1 tbsp Dijon mustard

1 tsp Worcestershire sauce

1 tbsp soy sauce

Salt and pepper to taste

8 ounces grated Gruyere cheese

1 tbsp freshly chopped parsley

Prepare caramelized onions by melting butter in a large skillet over medium heat. Add onions, one teaspoon salt and one bay leaf. Cover and cook for 10 minutes, stirring regularly.
Remove lid and cook until onions are a deep golden brown (20-25 minutes), stirring frequently. Add thyme and white wine and cook until the liquid has evaporated. Remove the bay leaf. Remove from heat and set aside.
Preheat the oven to 350 degrees.
Place half the bread cubes in six individually sprayed crocks. Alternatively, you can use a 9x13 sprayed baking dish.
Evenly distribute half of the caramelized onions and half of the shredded cheese over the bread cubes.
Top with remaining bread and onions in layers.
In a large bowl whisk together the eggs, heavy cream, milk, mustard, Worcestershire, soy sauce and salt and pepper to taste.
Pour egg mixture over assembled ingredients and sprinkle remaining cheese. Bake for 25-35 minutes or until egg mixture is set and knife comes out clean.
Garnish with chopped parsley.