For the lamb marinade and sausages: Combine the oil, vinegar, honey and mustard in a large resealable plastic bag. Season with salt and pepper. Add the lamb to the bag and marinate in the refrigerator for at least 3 hours (or overnight).
Preheat the oven to 350 degrees F (180 degrees C).
Heat a heavy ovenproof skillet over high heat until hot. Meanwhile, pat the lamb dry and discard the marinade. Add the oil to the hot skillet, then brown the racks of lamb on all sides, about 3 minutes. Add the sausages, shallots and rosemary to the skillet and sprinkle with salt and pepper.
Transfer the skillet to the oven and cook until a meat thermometer inserted into the center of the lamb registers 140 degrees F (60 degrees C), about 25 minutes. Transfer the lamb and sausages to a platter and cover with foil to keep warm and allow the juices to redistribute. Discard the shallots and rosemary and reserve the skillet.
For the sauce: Add the veal stock to the skillet and bring to a simmer, stirring and scraping up any browned bits from the bottom with a wooden spoon. Let the sauce reduce for about 5 minutes or until it reaches the desired consistency. Whisk in the butter, if using, and season with salt and pepper.
Slice the lamb between the bones and serve with the sausages, Crispy Potatoes, a ladle of the sauce and a dollop of Spicy Red Pepper Jelly.
Heat the canola oil in a deep fryer to 250 degrees F (120 degrees C). Line a baking sheet with paper towels. Fry the potatoes for about 2 minutes to blanch them. Transfer to the prepared baking sheet to rest for 5 minutes. Raise the oil temperature to 350 degrees F (180 degrees C). Fry the potatoes again until golden brown, about 2 minutes. Transfer to fresh paper towels to drain.
Transfer the potatoes to a large bowl and toss with the paprika, smoked salt, red pepper flakes, chives, garlic, parsley and a drizzle of olive oil.
Spicy Red Pepper Jelly:
Pulse the bell peppers and chile pepper in a food processor until finely chopped. Transfer to a saucepan and add the sugar, vinegar, ginger, salt and lemon zest and juice. Bring to a boil over high heat, then reduce the heat and simmer until it thickens, stirring occasionally, about 25 minutes. Pour the jelly into a jar. Let cool, then store in the refrigerator.