Place all of the meatball ingredients in a large bowl.
Using your hands, with gloves or not, [the best way] or a spoon, completely combine the meatball ingredients. The mixture should be completely uniform, with no pockets at all of unmixed ingredients.
Using a 2 ounce disher, large cookie scoop, or just eyeballing it, portion the mixture into large meatballs. Roll each meatball between your hands until they are round and packed together.
As you roll them, place the meatballs in a large skillet, so that each one touches the bottom, and there is a small bit of space between them.
Make the sauce
There are two ways to make the sauce, as I mentioned in the post. You can add all of the sauce ingredients to a large measuring cup or medium bowl, and mix everything together. Pour the resulting mixture evenly over the meatballs.
OR
You can evenly distribute each of the sauce ingredients over the meatballs, one at a time.
Cover the pan and place over medium heat. Keep an eye on it, until it comes up to a simmer. Don't stir it, or the meatballs will start to fall apart.
When it comes up to a simmer, lower the heat slightly, and keep covered.
After 10 minutes, stir gently and allow to cook for about 35 minutes more. Keep the heat low enough to maintain a simmer, and stir gently a couple of times to make sure nothing is sticking. If you have any sticking, lower the heat a bit. You add a little more stock if the sauce seems too thick.
The dish is done when you can see cooked rice sticking out of the sides of the meatballs, and the sauce is thickened. If you want to be absolutely sure it's done, you can cut open a meatball, to make the rice is cooked. 45 minutes total cooking time is usually plenty of time though.
Serve hot, with a side veggie or salad and maybe some bread to sop up the extra sauce.
*See notes for cooking Porcupine Meatballs in the oven.
Notes
*This dish can be cooked in the oven, which is even easier than using a skillet. You need a flat bottomed baking dish so that all of the meatballs have room to sit on the bottom, The sides have to be high enough to hold the sauce. Something like this will work nicely. Roll the meatballs, and place them in the bottom of the dish. Mix the sauce and pour over evenly. Place the lid on the dish, and put it in a 350° preheated oven. Bake for about an hour, carefully stirring every 20 minutes or so. Leftovers can be kept in the refrigerator for 2 or 3 days. This doesn't freeze very well, as the rice will become mushy.