Place potatoes in a large saucepan, cover with water and bring to a boil over high heat. Reduce the heat to medium-low, and simmer until the potatoes are tender but still firm, about 15 minutes. Drain. Allow to cool. Peel and cut into 1-inch cubes.
Meanwhile in a mixing bowl, whisk together pesto, lemon juice and extra virgin olive oil. Add potatoes, onions and peppers. Toss gently to coat. Salt and pepper to taste. Best served warm or at room temperature.
Note: Before serving you may want to add a little more extra virgin olive oil to give the dish additional shine.