Combine potatoes, stock, wine and garlic in medium nonstick skillet over high heat. Boil until almost all liquid evaporates and potatoes are tender, stirring occasionally, about 12 minutes. Mix in Parmesan cheese and butter. Season with salt and pepper. (Can be made 2 hours ahead. Let stand at room temperature).
Preheat oven to 350ºF. Heat oil in large ovenproof skillet over medium heat. Season fish on both sides with salt and half of peppercorns. Add to skillet; cook 5 minutes per side. Transfer skillet to oven and bake fish until cooked through, about 5 minutes.
3Transfer fish to plate. Tent with foil to keep warm. Place same skillet over medium heat. Add brandy and boil 30 seconds, (mixture may ignite). Add stock, cream and remaining crushed peppercorns and boil until reduced to 1cup, about 5 minutes. Remove from heat and whisk in 1 Tablespoon butter. Season to taste with salt.
4Meanwhile, rewarm risotto over low heat. Divide between 2 plates. Top with fish and spoon sauce over.