Roasted Radish and Potato Salad

Name: Roasted Radish and Potato Salad
Ingredients: For the salad; 10-15 radishes (your favorite variety, rinsed, trimmed, and halved or quartered depending on size); 3 medium Yukon potatoes (rinsed and cut into bite size pieces; 1/4 red onion (thinly sliced); olive oil; sea salt and freshly ground black pepper; Dill Sour Cream Sauce; 1/2 cup sour cream; 1/2 cup buttermilk; 1 tablespoon Dijon mustard; 1 tablespoon white wine vinegar; 1 clove garlic (minced); 1/2 lemon (juice); 2 tablespoons dill (finely chopped); Salt