Slice zucchini lengthwise into 1/8-inch thick slices. (For best results, use a mandolin slicer)
Sprinkle zucchini slices very slightly with salt and lay between two layers of paper towels. Let them rest for about 15 minutes to allow excess moisture to drain.
Preheat oven to 350 degrees Fahrenheit.
In a medium bowl, stir together the ricotta, egg, Parmesan, garlic, salt, Italian seasoning, and fresh basil.
Spread 1 cup of the marinara sauce in the bottom of an 8.5 x 11-inch baking dish.
Spread a spoonful of the ricotta mixture onto a slice of zucchini. Roll it up and place it into the baking dish. Continue until you've used all of your ingredients and the baking dish is packed with zucchini roll ups placed side by side.
Spread the remaining cup of sauce over the top of the roll ups and sprinkle with mozzarella.
Bake the roll ups at 350 degrees Fahrenheit for 25 to 30 minutes or until the cheese is bubbly and beginning to turn golden.