Store individual ingredients separately to maintain freshness. To prevent soggy bread, toast rolls until crisp and dip quickly. Warm sliced beef gently; boiling it in au jus can toughen it. Simmer au jus longer to concentrate flavors for a richer dipping sauce. Consider Swiss, mozzarella, or no cheese as substitutions. Use other sturdy rolls or any lean, thinly sliced cooked beef for convenience. For extra richness, use good quality store-bought beef consommé instead of stock. For healthier options, opt for low-sodium beef stock, whole wheat or gluten-free rolls, and lean roast beef.