Bring a pot of water to a rolling boil and separately blanch (about 10 seconds) the snow peas and carrots. Cool off quickly by shocking in ice water, drain and pat dry.
Combine in a bowl the snow peas, radish, carrots, red onions, mint and feta cheese.
In a shaker bottle combine the vinegar, mustard, and olive oil. Add salt and pepper to taste. Shake very well and reserve. Pour dressing over the salad and toss to coat everything evenly. Serve and enjoy!