Easiest

We like this:

Take a hunk of Beef (about 3 pounds)I usually use Chuck Roast but any cut of meat will do.(usually the cheapest I can find)
1 packet dry Onion Soup Mix (I use Liptons)
1 can Mushroom Soup (I use Campbells)

Pour undiluted canned soup in roasting pan, Sprinkle dry soup mix over, stir together, dip meat in mixture and turn over.
Put in SLOW oven (150 - 200 degrees) and let it cook all day. Check after a couple of hours to make sure it's not cooking too fast.
This can be done in a crockpot also but I've always done it in the oven.
The juices from the meat mix with the soup mixes and makes gravy. If you like more gravy or use a bigger cut of meat, just double the soups.
This is what I call a DUMP recipe. Basically you can just dump all ingredients in the pan without doing anything and it will turn out fine.