Sprinkle the salt, pepper and garlic evenly onto all sides of your roast.
Place the roast and 3 tablespoons of the beef tallow into sealer bag and seal it up.
Place the sealed bag into a sous vide water bath set at 130 degrees and let it cook for at least 4 hours, preferably 8.
Remove from the bag and pat dry. Put the juices from the bag into a sauce pan along with the rest of the au jus ingredients. Simmer for 30 minutes, and then strain out the vegetables from the au jus and set aside for serving.
Melt some more beef tallow in a pan on the stovetop over medium-high heat. Sear the roast on all sides until it is brown.
Let rest for 10-15 minutes before slicing.
Shave the roast into the thinnest slices you can.
Butter the rolls and toast on the inside. Place generous portions of the shaved venison on a preheat griddle and pour a little of the au jus over the top. Top with two slices of the cheese and cover with a dome until melted.
Put the meat into the toasted rolls and serve with extra au jus for serving.