Manicotti “Pancakes”
In a blender, combine the flour, eggs, water, and salt. Blend until smooth and let sit for 10 minutes.
In the bottom of a 10-to-12-inch nonstick skillet over medium-low heat, pour in enough batter to form 1 thin pancake. Cook until its underside is golden and the top changes color from milky to light yellow, about 1 minute. Do not flip, but cut in half and remove with a spatula to a large plate. Repeat with the remaining batter. You should have 18 to 24 manicotti “pancakes.”
Marinara Sauce
Pour the tomatoes into a large bowl and crush with your hands. Pour 1 cup water into the can and slosh it around to get tomato juices; reserve.
Heat the oil in a large skillet over medium heat. Add the garlic and, as soon as the garlic is sizzling but before it starts to brown, add the tomatoes and then the reserved water, salt, and oregano. Simmer the sauce until thickened and the oil on its surface is a deep orange color, about 15 minutes. Add more salt and oregano to taste and set aside.
Filling
Preheat the oven to 400°F.
In a large bowl, combine all the filling ingredients. (Cooked chicken or hamburger can be mixed into the filling, if desired.) Spoon some of the filling into each pancake, roll it up, and place seam down in a greased baking pan. Repeat with the remaining filling and pancakes, placing them side by side in the pan in a single layer.
Cover the pan with aluminum foil and bake for about 20 minutes. Remove the foil, spoon on the Marinara Sauce, and bake uncovered for about 15 minutes longer. Serve 2 or 3 manicotti, per person, topped with Parmesan and chopped fresh basil.