Note: The corned beef cooks for 7 to 9 hours. If you don’t have all day to roast it, feel free to sub store-bought.
For the toast:
- Render sliced corn beef in sauté pan over medium heat to warm through until slightly crispy.
- Toast bread to golden brown, then turn toaster or oven setting to broil. Slather toast with mustard and add cheese. Place under broiler a few seconds, until cheese melts.
- Over melted cheese, pile sauerkraut, beef, and egg. Garnish as you like with chives, espelette powder, drizzle of oil, and fleur de sel.
For the corned beef:
- Preheat oven to 225 degrees. In large sauté pan, sweat onion, carrot and celery in oil until softened. Add garlic and cook until raw garlic smell goes away.
- Pour mirepoix into roasting pan, add thyme, rosemary, and beef. Add beer. Roast in oven for 7 to 9 hours, basting and turning at regular intervals.