Blanch shelled peas in salted boiling water for 1-2 minutes. Drain and shock with ice water, drain peas on a cloth towel. Save a little of salted cooking water and set aside.
In a food processor, process peas, Romano cheese, lemon zest, lemon juice, basil, olive oil, salt and pepper till smooth, about 1 minute add water 1 tsp at a time. Process until smooth. Transfer to a bowl to chill.
Serve on a grilled baguette or with spring crudités