Begin the night before by shaking Adoph's meat tenderizer over the roast on all sides and rubbing it in. Place roast in a zip-lock bag and pour 1/3 bottle of Lawry's Sauce over it. Massage the bag to distribute evenly. Place the closed bag in the refrigerator overnight.
The next morning (by 8am to eat at 6pm, or 9am to eat at 7pm), spray the crock with Pam. Turn to "low"/10 hour setting.
Melt 2 T. butter in a skillet. Brown roast carefully on all sides. BE VERY CAREFUL TURNING THE MEAT! You can use tongs, but make sure they don't slip! The splash of butter/fat can burn terribly. (Trust me!)
To the crock, add the carrots, potatoes, and onions.
Place the browned roast on top of the veggies. You may need to move the veggies to the sides and make a "well" for the roast to sit in.
Don't waste those gorgeous fryings in the skillet! Turn heat to medium high, and deglaze the pan with the can of beef broth, and the remainder of the Lawry's sauce. Stir carefully with a wooden spoon to loosen the bits until it comes to a boil.
Carefully pour the sauce in the pan over the meat and veggies in the crock pot. (This is the secret to the roast's savory favor!)
Put the crock's lid on, but don't lock it down.
After cooking for 10 hours on low, turn off crock and remove the meat to a serving platter to rest before "forking" it. (I'd say "cutting" it, but I think a knife won't be necessary.) Cover to keep warm.
With a slotted spoon, retrieve the veggies and move to a serving bowl. Cover to keep warm.
Into a large measuring cup, pour liquid from the crock; skim excess fat from liquid. If necessary, add enough water to measure 2 cups. Pour into a 2 qt. saucepan.
In a tightly covered container, shake 1/2 cup cold water and the flour until blended smoothly; gradually stir into liquid. Heat to boiling, stirring constantly. Boil and stir for 1 minute.
Serve gravy with beef and veggies.