In a large Dutch oven, boil potatoes over medium-high heat until fork tender. Drain; set aside to cool.
While potatoes are boiling, place corn, green beans and bacon on a parchment-lined baking sheet. Bake 20 to 25 minutes, stirring halfway through until bacon is cooked through and vegetables are slightly charred.
In a small bowl or jar, mix mayonnaise, mustard, garlic, lemon juice, chives, salt, and pepper.
To assemble potato salad, combine potatoes, corn-green bean-bacon mixture, mayonnaise dressing and Emmentaler cheese cubes in large bowl. Mix well. Garnish with radish slices and additional chives, if desired. Refrigerate before serving.