Prepare the crepe batter: In a blender, place the flour, milk, water, butter, eggs, and salt, and blend until the dough is very smooth, about 1 to 2 minutes. Transfer to a bowl and chill for at least 30 minutes.
While the crepe batter chills, make the filling. Bring 4 cups of water to a boil and add salt. Clean any thick stems from the spinach. Plunge all of the spinach into the boiling water pushing them in, and cook until barely softened, about 1 minute. Pour the spinach into a colander and press to remove any excess liquid. Let the spinach dry for 5 minutes, then chop roughly.
In a medium saucepan, melt the butter; add the garlic and cook until it just starts to turn golden, about 1 minute. Add the shallot and cook until soft, another minute. Add the spinach and stir. Remove the pan from the heat and place in the corner of the stove.
In a small saucepan, heat the chicken stock. Place the flour in a small bowl, add a few tablespoons of the chicken stock and whisk well. Pour back into the pot chicken stock, and cook whisking constantly until it starts to thicken. Season with salt, pepper, and nutmeg. Mix the spinach with the chicken sauce; the spinach should continue bright green, lightly moistened by the sauce. Taste again and add more seasoning if necessary.
To make the tomato sauce: In a medium saucepan melt the butter over low heat and add the garlic; cook until it just begins to turn golden. Add the shallot and cook until it gets soft, about 2 minutes. Add the tomatoes and cook, stirring frequently until it begins to soften, another 2 minutes. Add 1/2 cup water, bring to a boil, and the tomato sauce. Season with salt and pepper. Set the heat on medium, and cook until it’s nice and tasty, about 10 to 15 minutes.
To assemble the enchiladas start by cooking the crepes. Heat a small nonstick pan over low heat. Add a film of olive oil, about 1 teaspoon, and swirl the pan around to coat the bottom. Pour 2 to 3 tablespoons of the batter and immediately swirl the pan to spread the batter into a thin even circle. Cook until the bottom side turns gorgeously golden brown, about 2 minutes (take a peak), then flip and cook the other side until you see black spots, another 2 minutes (the second side is never as pretty as the first). Transfer the crepe into a sheet pan and repeat until all the batter is used. You should have about 10 crepes.
Preheat the oven to 350F. Fill each crepe with 2 to 3 tablespoons of spinach, then roll tightly. Arrange all of the crepes in a baking dish, and spoon some tomato sauce over. You might not need all of the tomato sauce. Generously sprinkle Parmesan on top (At this point you can cover the dish with plastic wrap and keep refrigerated for 2 days.) Bake in the oven until the cheese is melted, and the sauce is bubbling about 12 minutes. Serve hot.