Bring a pot with three quarts of water and lentils, to a boil. Reduce heat to a low and let it simmer for about 20 minutes.
In a bowl, combine ground meat, bread crumbs, garlic, half dice onions, salt & pepper. Work the meat with your hand. to combine all ingredients together.
Out of prepared meat, roll out equal sized meatballs. You can use a small ice cream scoop to create those equal pieces.
Preheat a skillet with a few tablespoons of light olive oil, place meatballs on the skillet. To turn meatballs, lift up the skillet and shake it from side to side, this would help for meatballs keep their round shape. Remove meatballs and set the skillet aside.
Dice the other half of the onion into small cubes and dice scallions into small pieces. Using the same skillet you've used to cook meatballs, cook onions until they are softened.
Add canned tomatoes to the cooking onions, cook until tomatoes are softened. Add tomato mixture into the cooking lentils, let it simmer for about 10 minutes.
Blend soup until the texture is creamy. Place blended soup back into the pot; now you can add those meatballs, which were sitting out for a while. Let soup simmer on low heat for another 10 minutes.
Soup is best when it's served warm. You can refrigerate the soup for several days, just reheat before serving.