INGREDIENTS
1/4 cup
extra-virgin olive oil
3 tbsp
white wine vinegar
2 tbsp
grainy mustard
3/4 tsp
freshly ground black pepper
1/4 tsp
kosher salt
1 1/4 lb
multicolored fingerling potatoes, halved
1/2 cup
thinly sliced red onion
2 tbsp
finely chopped fresh chives