I have not made this dish yet as I just found it in our Wednesday paper's Food section. It sure sounds delicious and I plan to make it this weekend. It does call for Gruyere cheese and if you cannot find that cheese or think it might be too pricey, I believe Swiss would be a good substitution for it.
Preheat oven to 325 degrees. Place bread on a large baking sheet in a single layer, and bake until dry and crisp, about 4 minutes total. Turn slices over at 2 minutes for even baking. Remove from oven and allow bread to cool. When bread has cooled, butter slices on one side using 3 tablespoons of butter. Melt remaining 2 tablespoons of butter in nonstick skillet over medium heat. Saute shallots until fragrant and translucent. Add spinach, 1/2 tsp. salt and 1/4 tsp. pepper, and saute another 2 minutes. Transfer contents to a bowl and set aside. Add wine to skillet. Increase heat to medium-high, and deglaze pan until wine is reduced to 1/4 cup. Take off heat and set aside.
Coat an 8 inch square baking dish with cooking spray. Arrange four toasted bread slices, buttered side up, in a single layer. Sprinkle half of the spinach mixture and 1/2 cup of the Gruyere evenly over bread. Arrange remaining 4 bread slices in a single layer over cheese, buttered side up. Pour remaining spinach mixture and another 1/2 cup Gruyere evenly over bread. Set aside.
Whisk together eggs, reduced wine, Half and Half, 1/2 tsp. salt and 1/4 tsp. pepper in a large mixing bowl. Pour egg mixture evenly over bread layers. Tightly cover baking dish with plastic wrap and place in refrigerator for at least one hour or overnight. Before baking, remove dish from refrigerator and let stand at room temperature for 20 minutes. Make sure oven is preheated to 325 degrees. Remove plastic wrap from dish and sprinkle remaining 1/2 cup Gruyere evenly over the top.
Bake for 50 - 55 minutes or until strata is puffed and edges have slightly pulled away from the sides of the dish. Remove from oven and allow to cool for five minutes before cutting and serving.
This sounds like a lot of work but I really don't think it is and the picture is delicious looking!!