Wasabi, that greenish Japanese horseradish familiar from sushi bars, has many more uses than just accompanying raw fish. It adds a spicy edge to all sorts of foods without the heaviness of bottled horseradish.
You can find it in specialty and Asian markets in two forms: ready-to-use paste in a tube or powder in small tins. To use the powder, you make it into a smooth paste with water, as you’d do with dry mustard. The ready-to-use paste has a slightly sharper flavor and a deeper green color, and it’s my preference in these recipes.
As with all sharp seasonings, it’s best to start with a small quantity of wasabi and add more after tasting.