Nobody is indifferent to sea urchin roe: You either love it or hate it. Personally, its rich and sexy taste is my favorite flavor on earth. Until I tried the extraordinary mousse invented by Jean-Georges Vongerichten, I preferred it raw. Now I know better. The best sea urchin roe comes from southern California, and is sold in little wooden trays at Japanese markets. It is extremely fragile. It's important to use very fresh roe with a clean, ripe, rather fruity scent.