In a large skillet, heat healthy cooking fat over medium heat. Sauté onions until soft and translucent (approx. 5 minutes).
Add carrots and sauté for another 3 minutes. Add tomato sauce and increase heat to high. Simmer for a few more minutes to thicken sauce, stirring often.
Reduce heat to medium. Spoon half of this onion-carrot sauce in a bowl and set aside.
To the remaining sauce still in the pan, add shredded cabbage and cook for 4-5 minutes to soften and release juices. Add cauli-rice and continue to cook for additional 2-3 minutes. Take off heat and allow to cool.
Preheat oven to 425F degrees. Spread half of the reserved sauce in a 9X13 casserole dish.
In a large mixing bowl, combine ground poultry, sautéed vegetables, eggs, and seasonings and mix well.
Scoop 1/2 cup of meat and vegetables mixture and form into oblong meatballs. Spread remaining sauce evenly over the cabbage rolls.
Cover and bake for 45 minutes. Remove cover to broil for 5-10 minutes (watch carefully) to reduce the liquid and brown the tops.