Add 800 g Potato to a pan of boiling water and boil until soft, about 15 minutes.
Heat 1 tablespoon Olive oil in a large pan and cook 800 g Sausages according to the packet instructions - usually 10-12 minutes. Once cooked, set aside.
Add 1 Onion and 10 Mushrooms to the pan. Cook until softened, about 5 minutes. Add 2 tablespoon Plain flour, 550 ml Beef stock and 1 teaspoon Marmite. Simmer for a further 3 minutes.
Once the potatoes are cooked, drain and add 20 g Butter, 4 tablespoon Whole milk and 1 tablespoon Dijon mustard. Mash until you get your desired consistency.
Chop the cooked sausages into bite-sized pieces and add to the pan of vegetables with 415 g Baked beans and 4 sprig Fresh thyme. Mix well.
Preheat your oven to 200°C/180°C(fan)/400°F/Gas 6.
Transfer the sausage/vegetable mix to a large baking dish.
Spread the mashed potato over the top of the sausage mixture then sprinkle with 50 g Mature cheddar. Cook in the oven for 30 minutes until the cheese has melted.
If you are using sausages with a high fat content, you might not need to add any oil to the pan to cook them in.
Make sure the baking dish you are using it big enough, so everything doesn't spill out when it is cooking in the oven.
For something a little different for this pie topping, why not try adding filo pastry on top for a crispy topping.
For a lower carb alternative to the mash, half the potatoes and add cauliflower and mash it all together.
Add some extra flavour by using a can of flavoured beans like BBQ beans or Mexican beans.
For a richer flavour, add a splash of red wine at the same time as the stock.
Cool the meat mixture a little before adding the potatoes. This allows it to thicken up, and also makes it easier to spread the potatoes on top. The creamier the potatoes, the easier they are to spread.