If you like a deeper flavor, sear the rump roast in a hot skillet with a little oil for a few minutes on each side before placing it in the slow cooker, though it’s not necessary. You can swap the cream of mushroom soup for cream of celery or cream of chicken if that’s what you have in the pantry. For a more peppery, pot-roast style, add 1 teaspoon of dried Italian seasoning or a generous pinch of black pepper along with the onion soup mix. If you prefer a thicker gravy, stir 1 tablespoon of cornstarch into 2 tablespoons of cold water and mix that into the hot cooking liquid at the end; turn the slow cooker to HIGH and let it bubble for 10 to 15 minutes until thickened. To stretch the meal, add a pound of peeled carrot chunks and halved baby potatoes around the roast before cooking, keeping in mind they’ll soak up some of the gravy. Leftovers can be chilled, then sliced and reheated in the gravy for hot beef sandwiches or served over toast for an old-fashioned open-faced supper.