The recipe below is just exactly as I copied it off of Good Morning America. I think just 1/2 stick of butter would be plenty. I used a sirloin tip roast, one of the toughest cuts of beef you can find, and it came out fork tender. I did cook it all day on low in the slow cooker, though.
“Sometimes we use chuck, sometimes sirloin tip, sometimes rump.”
3 to 4 pound roast, your choice of cut
1 stick butter
1 package au jus gravy mix
1 package Hidden Valley Ranch dressing mix (dry)
Pepperoncini peppers, number to your liking and a little juice
1. Sometimes we sear it. Sometimes we don’t.
2. Put roast in slow cooker. Add other ingredients. Salt and pepper if you like.
3. Cook on until tender.