"Most sea urchin roe is exported, which is a great shame," says Luke Burgess. "When it's fresh, it's like a taste of the sea. This pairing with clams makes a quick and simple snack. Tomatillos, a tomato relative, are a classic salsa ingredient in Mexico. They're sold canned in Mexican grocers, although you may be lucky enough to find them fresh at a farmers' market."
Note Fennel pollen is available from Herbie's Spices and select delicatessens.