SOUP: TOSS cauliflower and potatoes with oil; spread onto bottom of parchment paper-lined sheet pan. Roast in 375ºF convection oven 15 min. or until lightly browned. Transfer to saucepan. Stir in mustard, half-and-half, chicken stock and curry paste; simmer on medium heat 30 min., stirring occasionally. Process in small batches with food processor or blender until very smooth. Season with salt and pepper.
GARNISH: CUT 1 large flat slice (about 2 inches in diameter) off each of 32 cauliflower florets (or off each of 4 florets for trial recipe); cut remaining cauliflower into small florets. Sear cauliflower slices and florets in hot oil in skillet on medium-high heat until lightly browned. Remove from skillet; set aside. Add scallops to skillet; cook 1-1/2 to 2 min. on each side until lightly browned and opaque.
FOR each serving: Ladle 8 oz. soup into bowl; top with 1 each cauliflower slice and scallop. Spoon about 1 Tbsp. small cauliflower florets around the scallop.