Divide the grass fed ground beef into 4 portions and gently form them into patties. I season both sides generously with salt and pepper. (Tip: I didn’t mix in the seasoning because I didn’t want to overwork the meat. Too much manhandling can lead to tough pucks.)
Place the seasoned burgers on top of a plastic-wrapped plate and cover the plate with another sheet of plastic wrap. (Tip: If you don’t line your plate with plastic wrap first, it’ll be difficult to remove the frozen patties.)
Put the plate in the freezer and freeze the patties for at least 2 hours.
Once the patties are frozen, vacuum seal each patty and store them in the fridge until you're ready to cook them.
Heat the SousVide Supreme to 132°F and dunk in the burger packets. Burgers take at least 30 minutes to cook but you can leave them in the water for up to 12 hours.
When the burgers are finished cooking, take them out of their packets and dry them with paper towels.
Heat a couple tablespoons of bacon grease in a large cast iron skillet and sear each side for about a minute.
Put the burgers on a wire rack on top of a foil-lined baking sheet and use your kitchen torch to even out the browned bits.
Top the burgers with your favorite toppings and serve them over salad greens!