Cook potatoes in boiling water until tender, 15 to 20 minutes.
6 to 8 russet or sweet potatoes
Drain the water and let the potatoes cool.
In a bowl, combine the mustard, lemon juice, vinegar, and olive oil, and season to taste.
¼ cup grainy or old-style mustard, 1 tbsp. fresh lemon juice, ¼ cup olive oil, 1 tbsp. apple cider vinegar, Sea salt and freshly ground black pepper
In a salad bowl, add the diced potatoes, bacon slices, onion, parsley, and chives.
4 to 6 bacon slices, 1 red onion, 1 tbsp. fresh chives, 3 tbsp. fresh parsley
Drizzle the grainy mustard on top and gently toss everything until well-coated.
¼ cup grainy or old-style mustard
Refrigerate until ready to eat.