- Sauté the diced onion over medium high heat, stirring occasionally, until translucent. 
- When the onion is just starting to brown, add the ground beef and break up into smaller pieces. Stir often, and continue to cook until the liquid starts to dry (if not using Bisto, add a tablespoon of flour at this time). 
- Add enough water, just to cover the ingredients, and simmer. At this point, add about salt, one OXO cube (or 1 tsp Beef Better than Bouillon), Bisto granules, Worcestershire Sauce, and some ground black pepper to taste. 
- Preheat oven to 375ºF (190ºC). 
- Continue to simmer the meat over medium heat for about 5-10 minutes, then taste. Add more salt if needed, then remove from heat. 
- Ladle the beef and gravy into oven safe ramekins or bowls to make individual cottage pies, or just one large dish. Spoon (or pipe) mashed potatoes onto each dish to cover completely. Add shredded Cheddar cheese on top, if desired. 
- Place dishes/ramekins onto a rimmed baking sheet and bake until bubbly and the potato is a little browned, approximately 25-30 minutes. You can finish off the pies under the broiler if you like them to have more crispy, and brown tops.