Cook peas in a saucepan of boiling salted water just until they turn a brighter shade of green, about 30 seconds. Drain in a colander and rinse under cold water to stop cooking.
Cut halved cucumber and radishes crosswise into 1/4-inch-thick half moon slices.
Toss peas, cucumber, radishes, and sesame seeds with vinegars and season with salt and pepper.
Recipe courtesy of Gourmet Magazine