The diet should be comprised of:
- some organ meat
- vegetable matter
- (optional) cultured dairy, eggs
- (occasional, optional) manufactured treats
It does not need to be complicated, expensive, messy, or inconvenient. Bottom line, it is the closest to species-appropriate diet as one can get.
There are ground products available to thaw and serve, or you can do some self-education and find easy, inexpensive ways to ensure your dog is getting maximum nutrition, enjoyment, and variety. Either way, you can do much better than anything you will find in a (typical) vet's office or pet food aisle.