Combine the first eight ingredients in a blender and blend on low. Slowly add the oil, then turn the blender to high and blend until the mint is fully pureed—resulting in a beautiful, creamy, bright-green dressing.
To shell the peas, snap off the stem hat, zip the string down the side to open the pod and pop out the sweet green orbs.
Bring a large pot of salted water to a rolling boil, then blanch the peas for 2 to 3 minutes. Drain and immerse in a cold-water bath.
To serve warm, return the peas to the pot on low heat and dry them out a bit. Toss with the dressing and chopped chives.
To serve cold, skip the reheating stage and toss the drained peas with the dressing and chives.