1) Place the baby new potatoes in a large saucepan filled with cold salted water and cook on medium heat until tender, about 20 minutes.
2) While the potatoes are cooking, place a colander over the boiling water and blanch the green peas for about 45 seconds.
3) Drain the potatoes, transfer to large bowl and set aside to cool for a bit. Once the potatoes are cooled slightly, add the red onion, dill, chives, mayonnaise and peas. Drizzle with lemon juice and toss gently to coat. Season with salt and pepper, to taste.