Preheat the oven to 350°F, 177°C or gas mark 4. Salt the short ribs.
In a Dutch oven brown the short ribs on all sides. Remove the ribs from the Dutch oven and place on a plate.
Add the butter and reduce the heat to medium and add the carrots, celery, leeks, shallots, and onions. Cook until the onions start to brown, about 10 min.
Add the tomato paste and cook for another 2 minutes to brown the paste.
Add Irish whisky, brown sugar and garlic to the Dutch oven and cook for 2 minutes and add the ribs, thyme, and beef broth.
Cover and place in the oven for 2½ hours
Remove the ribs from the broth, strain the broth and then reduce over medium high heat. Drizzle the reduction over the ribs.