Sprinkle taco seasoning over the beef. Mix the taco seasoning into the beef. Do not add water.
Cover and cook on high for 2-3 hours, stirring occasionally until the ground beef is fully cooked (160 degrees F in the center of the slow cooker with a meat thermometer).
To make more than 3 pounds of taco beef, add up to 3 more pounds of ground beef and 3 more packets (12 Tablespoons) of taco seasoning (1 packet or 4 Tablespoons per pound of beef).
Cook, stirring occasionally until the meat is cooked to 160 degrees F.