Mix the beer sauce sugar and garlic together in a bowl and set aside
Put brisket in baking pan fat side up
Pour the sauce mixture over the beef and cover with foil
Bake at 325 for 3 12 hours then remove foil and bake for another 12 hour After the brisket has cooled slightly remove fat and discard Refrigerate and cool completely can be overnight then slice as thinly as possible
Cover slices of beef with sauce and microwave to desired temperature