Pea,Feta and Mint Salad

My mother used to make very bland all green salads but this has to be one of the best all green(except for the onion and feta) salads I've tried.
Again from Bill Granger's latest cookbook,Every Day.

Serves 4

200g peas
3T olive oil
1 onion finely diced
2 t Dijon mustard
1 T red wine vinegar
1 T honey
sea salt
freshly ground black pepper
35g pistachio nuts,roughly chopped
large handful fresh mint leaves
50g snow pea leaves or baby english spinach
75g feta cheese,crumbled

Blanch the peas in boiling water for 2 minutes,or until they are just tender and bright green.Refresh immediately under cold water.Heat a small pan over medium heat.Add 1 tablespoon of the oil and cook the onion,stirring for 5 minutes or until soft.
Whisk together the mustard,remaining olive oil,vinegar and honey and season with salt and pepper.
Mix the onion,peas and pistachios in a salad bowl and pour the dressing over the top.Add the mint and snow pea leaves and gently toss through the salad.Sprinkle with feta to serve.