Grapefruit frozen ahi

I am playing around with some ahi because it will be gone next week. We have experimented alot with freezing purees onto food with liquid nitrogen. I think one of my favorites is creme anglaise frozen on cherries. It is like eating a impossible frozen bon bon that melts back to creme anglaise instantly in your mouth. Today we froze a honey-wasabi- grapefruit puree thickened with little xantham on the rare tuna. The tuna remains tempered while a popsicle like coating is made on the outside. We topped it with some kiwi and pickled ginger jelly