
In a small saucepan, add the potatoes and enough water to cover them completely. Bring to a boil over high heat, reduce heat to low, cover, and simmer for 8 minutes or until the potatoes are cooked through. Carefully drain the water and set aside.
Add the frozen mixed vegetables to a medium microwave-safe bowl and heat them in the microwave on high for 4-6 minutes, stirring halfway through, until fully thawed. Set aside.
Whisk together the mayonnaise, sour cream, Mexican crema, lime juice, pickled jalapeño brine, and salt in a small bowl.
Add the cooked potatoes, thawed mixed vegetables, shredded chicken, and mayonnaise mixture in a large bowl. Toss them together to combine.
Taste and season the ensalada with more salt or pickled jalapeño brine if desired. Refrigerate for 1-2 hours or until chilled.
Serve with saltine crackers, on tostada shells, with tortilla chips, or in a sandwich.