Method
Prep:20min  ›  Cook:20min  ›  Ready in:40min 

1. For the gravy: Melt butter in sauce pan at medium heat, then add the onions, and cook until just soft and translucent, but not browned. Add the flour, and stir until the onions are coated evenly, and the flour is no longer visible. Add stock and Guinness®, and bring to the boil, then reduce immediately to a medium low heat. Stir constantly and cook until gravy is thick. Reduce to lowest heat possible while cooking the rosti, stirring occasionally.
2. For the rosti: On medium high heat, bring a pan of water to the boil. Add the potatoes, and cook for 5 minutes, or until fork tender.
3. Add oil and butter to a frying pan, and bring up to medium or medium low heat.
4. Remove the potatoes from the water, rinse under cool water, allow to cool, then coarsely grate. Gently mix with the onions and garlic.
5. Grill the pudding until crispy on both sides. Top each black pudding slice with a slice of cheese. Take a fourth of the potato mix, and cover each cheese / black pudding slice.
6. Place the potato / black pudding bundles in the fat, and cook until browned on one side (5-8 minutes), then brown on the other side (same time frame).
7. Plate with gravy on the side.