There are whole Reddit threads on where to find the best frozen burger patties for grilling? There seems to be a certain amount of consensus on Reddit that the best frozen burger patty can be found at Costco, and I'm not sure I can dispute that. Costco has a good selection of frozen ground beef patties, and if you want to avoid beef altogether, they have other burger options as well, including one of my favorites, the frozen salmon burger Patty. Getty Images Getty Images4 to choose fromWhen you shop at your local Costco, you'll see four different choices for Kirkland brand frozen ground beef burger patties. (75/25) You will find the 75/25 burger patties grill up nice and moist on the inside and remember the chef's motto?