CP French Dip Sandwiches

3-4 lb rump roast
1 pkg. au jus mix (dry)
1 pkg. italian dressing mix (dry)
1 (10.5 oz) can beef broth
1 1/2 cups water
Green pepper,sliced thin (optional)
Onion, sliced thin (optional)
Hoagie buns, sourdough buns or your choice
Swiss Cheese (optional)

Place roast in crock-pot. Mix next 4 ingredients and pour over meat. Cook on LOW for 8-10 hours. Remove roast and if adding peppers and onions put those in the crockpot and turn on HIGH until peppers just start to get limp. Remove veggies and set aside. Reserve juice for serving. Slice meat thinly or pull apart. Pile meat on buns with optional veggies and cover with cheese. Wrap in foil. Heat in 350°F oven for 10 minutes. Serve on plate with cup of juice for dipping.