Start by bringing a large pot of salted water to boil.
Add in your potatoes and let cook for 15- 20 minutes or until they are fork tender.
When your potatoes are fork tender, drain and return to your cooking pot.
Add in butter, milk, salt and grated cheese.
Mash potatoes and check for seasoning and creaminess.
Add additional milk, as needed to preference.
To make the gravy, add the butter to a large pot and melt over medium heat.
Add in your sliced onions and stir continuously until they become soft, brown and caramelized. Sprinkle the flour over the onions and stir for 1-2 minutes to cook out the raw flour flavor.
Pour in your Guinness, sugar, spices and beef stock.
Increase your heat and bring to a soft boil.
Once boiling, reduce your heat and let simmer for 20 minutes.
Season to taste.
To prepare the sausages, melt 2 tablespoons of butter in a large saute pan over medium-high heat and add in your sausage links.
Add in your Guinness and drop a top over the saute pan to trap the steam and cook the sausages.
Stir occasionally until the links are browned on all sides.
Remove and add to simmer in your gravy.
Garnish with sage.