Remove outer leaves and slice leeks in half lengthwise. Wash leeks thoroughly to remove sand and dirt. Place leeks in a pot of boiling salted water for 5 minutes. Remove and pat dry. Preheat oven to 400°F. Place leeks in casserole dish or roasting pan. Drizzle with 2 tablespoons of olive oil, half the lemon juice, half of the lemon zest and season with salt and pepper.
Roast the leeks for 35 to 40 minutes, or until they are tender. Meanwhile, place a large sauté pan over medium high
heat. Add 1 tablespoon of butter and remaining olive oil. Season scallops with sea salt. When hot, add scallops in one layer starting around edge of pan. Sear for 2 to 3 minutes per side. Remove scallops from pan and set aside. Reduce heat to
medium-low. Add remaining butter and shallots. Sauté for a minute and then add rosé wine. When sauce has reduced by half, finish with parsley, remaining lemon juice and lemon zest and whisk. Season with salt and pepper. To serve, place a roasted leek in the middle of the plate, top with scallops and drizzle with herb butter sauce.