In a separate bowl whisk milk and eggs together until well mixed.
Add egg mixture to flour and pulse until dough comes together and away from bottom of the bowl.
Dump the pasta onto a lightly floured surface and knead to bring the dough together. Wrap in plastic and allow to rest a minimum of 1 hour. If you are going to let it rest more than an hour, place in refrigerator.
Roll out the pasta using your preferred method. On our pasta machine we roll to #5. Cut the pasta sheets into 4" wide (the length if up to you and the width of your casserole).
For the Meat Filling
If your italian sausage is in casings, remove the casing and brown the sausage and onion in a fry pan until cooked through and the onions are soft. Remove the meat from the pan and set aside.
In the same fry pan, add the greens and cook until they are wilted. You may have to do this in separate batches as to not overwhelm the fry pan. When wilted add to the meat mixture. At this point you want this filling to be cool enough to combine with the cheese mixture so you can either do this step earlier or place in refrigerator.
In a separate bowl combine cottage cheese (or ricotta), 1/2 cup parmesan and nutmeg. When the meat and greens have cooled, add them and mix well.
Simple Marinara Sauce
Add oil to a medium sauce pan set to medium low. When the oil is hot add the garlic and cook until fragrant and just turning brown.
Add the tomatoes, salt, sugar and pepper. Simmer for 10-12 minutes, stirring often.
Check for seasoning, add salt, pepper and sugar as needed.
Assembling the Cannelloni
Grease a 9" x 14" casserole. Ladle some of the marinara sauce in the bottom barely covering.
Place one of the pasta sheets on a flat surface. Using either a spoon or your hands place a good amount of filling, being careful to not overfill, down the middle of the pasta. Carefully roll the pasta and place in the casserole dish. Do this for the remaining sheets. If you have filling left over just sprinkle it over the cannelloni. Pour the remaining marinara sauce over the cannelloni and then sprinkle generously with grated mozzarella and parmesan. Cover with foil and bake for 30 minutes. Remove foil and continue baking for 10-15 minutes more, until the cheese is brown on top and the sauce is bubbly.