Made this using 1 large bulb fennel, about one pound and one large ripe Texas Red River grapefruit, supremed with no membranes. Blended 3/4 of the grapefruit with the cooked fennel. Garnished with freshly ground black Kampot pepper, grapefruit supremes, and lemon oil (HEB brand). Decided to enjoy a bowl hot and refrigerate the rest to enjoy chilled. Ended up eating the entire batch warm. Delicious. Certainly one of the best soups I have ever had.