Make the lemon oil: Place lemon zest, chilli flakes and olive oil in a small pan. Gently heat the oil and zest over low heat for a minute. Remove from heat and let infuse for 5 minutes. Strain the oil and reserve to cool.
Make the garnish: Blanch leek in a small saucepan of boiling salted water 3 minutes or until soft; drain. Place some of the leeks in center of each bowl.
Cook scallops: Heat remaining tablespoon oil in medium skillet over high heat. Sprinkle scallops with salt and pepper. Sear until brown and just opaque in center, about 1 minute per side. Place 1 scallop on top of leek in each bowl, and then top scallop with fish roe. Ladle the broccoli soup around the scallop, drizzle with a teaspoon of lemon chilli oil and sprinkle with chives.