Place the cut potatoes in a large saucepan and add cold water to cover by about 1 inch; generously season the water with salt.
Bring to a boil over medium-high heat and cook for about 8 minutes after boiling, or until a fork pierces the potatoes easily; drain and set aside.
Thaw the frozen diced carrots and peas and the corn if needed, then drain any excess water; you can thaw overnight in the fridge or follow package instructions to cook from frozen.
In a large mixing bowl, whisk together the mayonnaise, sour cream, lime juice, and jalapeño brine until smooth.
Add the warm potatoes, thawed vegetables, and cubed cooked chicken to the dressing and toss gently to combine so the warm potatoes help meld the flavors.
Season the salad generously with salt and black pepper to taste, then serve warm or cover and refrigerate until ready to serve.