Return the skillet to the heat and add 1 tablespoon of the oil. Add the carrots in a single layer, season with salt and pepper and cook over moderate heat, turning, until browned, about 5 minutes per side. Add the pearl onions, sprinkle with the curry powder and cook, stirring a few times, until fragrant, about 1 minute. Add the wine and simmer over moderately high heat for 3 minutes. Add the porcini powder and mushroom broth and bring to a boil. Transfer the skillet to the oven and braise the carrots for 1 hour and 15 minutes, turning once, until tender.