Bring a large pot of lightly salted water to a boil. While you wait for the water to boil, fill a large bowl with water and ice. Set the ice-water aside. Add the peas to boiling water and cook uncovered for 2 minutes. Drain and immediately place them in the ice-water for 2-3 minutes. Once cooled, drain the sugar snap peas and pat dry.
In a large bowl, gently toss the peas, radish, cilantro (or mint) and Sesame seeds together. Right before serving, dress with olive oil, lemon juice and white vinegar. Add salt and black pepper to taste. Toss to coat and adjust seasonings. Sprinkle with feta cheese and serve.