INGREDIENTS
3
Garlic cloves
1
bag Spinach, frozen
1
Yellow onion, chopped (about 2 cups), large
9
Eggs, large
2 tbsp
Dijon mustard
3/4 tsp
Black pepper
1/4 tsp
Nutmeg, ground
1 3/4 tsp
Salt
12 oz
Italian sandwich bread
3 tbsp
Butter, unsalted
6 oz
Gruyere
2 3/4 cups
Half-and-half
2 oz
Parmigiano-reggiano