The sauce can be made ahead of time and set aside: Heat 1 8-ounce can of low sodium sauce and 1 cup of water in a saucepan over medium heat. Stir in the garlic powder, basil and oregano. Turn the heat up to medium-high, then turn the heat down to low and let the sauce simmer for 5 to 10 minutes.
Preheat the oven to 350 °F and lightly spray a 9x13-inch baking dish with nonstick spray.
Boil a big pot of water, and cook the manicotti noodles according to package instructions. When the manicotti noodles are done cooking, transfer them to a plate to cool off.
While the noodles are cooking, spritz a skillet or large saucepan with nonstick spray. Add the chopped kale to the skillet and cook over medium heat until it starts to wilt. Sprinkle in 2 teaspoons of garlic powder and give it a good stir.
Set the kale aside to cool.
In a small bowl, stir together the cream cheese, cottage cheese, and 2 ounces of the mozzarella cheese.
Stir the kale mixture into the cheese mixture.
When the manicotti noodles are cool enough to handle, stuff them with the kale/cheese mixture.
Arrange the stuffed manicotti in the prepared baking dish. Pour the sauce evenly over the manicotti noodles. Sprinkle the remaining 1 ounce of mozzarella cheese on top.
Bake for 25 minutes. There's no need to cover the baking dish with foil, or anything like that.