In the Yorkie Health and Diet section of YT there is a "sticky" on homemade foods and treats. During Gracie's first year I cooked for her. I found that she would love the food when I first cooked it but she hated the left overs. When I stopped putting rice and oatmeal, flour and other grains in the food and replaced it with some lightly cooked sweet potato she started loving it fresh cooked or left over. That is how I ended up going with a grain free diet.
http://www.yorkietalk.com/forums/yor...od-treats.html
I also use a supplement called The Missing Link. The main one is:
Canine Nutrition | Dog Health | Dog Supplements | Dog Food Supplement | The Missing Link
The one that says for skin and coat was formerly the main product. It contains enzymes and nutrients that are normally lost when pet foods are subjected to high temps in order to kill any organisms that could breed bacteria while sitting on the shelf for months at a time.
There are some YouTube videos that show how to do home cooking and also how to prepare raw diets. I would consult with a holistic vet to get recommendations as well.
Dr. Michael W. Fox is very attentive to nutrition for dogs. He has some very interesting articles on the website. Maybe you could search through some of his info as well. He has multiple links to informative food information.
Dr. Michael W. Fox - Essays, Reviews, Articles on Pet Behavior, Care and Health