
You can buy either rice flour or potato flour and mix anything in it that is low in fat. You could use wheat flour too, but I don't.
To the flour add anything low in fat. Microwave or roast sweet potatoes, mash, and mix with the flour - or use any kind of veg your dog likes. You could also add any low-fat protein - buy turkey mince, precook it and drain off all the fat before adding it to the flour. Or, buy any canned fish that is not packed in oil - mush and add to the flour.
The mix should be moist enough to cling together - make walnut size balls - press down lightly to flatten - bake until lightly brown.
Freeze any your dog will not eat in 4 - 5 days and defrost when needed.