Dice a ¼ onion, heat up the olive oil in a saucepan and let the onion sauté for 10 minutes on low heat until soft and colorless.
Add 1 cup water and pinch of salt to the pan and bring to a boil.
Add 2 cup fresh peas boil 1 minute and transfer directly to a blender.
Blend on high for 1 minute, then pass through a strainer in to a container (preferably metal) sitting in an ice bath to cool very quickly and preserve the green color.
Once cool, season the puree with salt. It should be very thick and stand up on a plate.
You will only use about 1/2 cup of finished pea puree, but you need to make extra so it can puree in the blender.