Preheat the oven to 400 F. Place racks towards the bottom.
Wash and half the potatoes. Place in large pot with apple cider vinegar and then cover with water. Bring to boil and continue to boil for 12 minutes. Strain and pat dry. Toss potatoes with olive oil and sea salt and place on a baking sheet cut side down lined with parchment.
Roast in the oven for 10 minutes and then reduce temperature to 350 F / 175 C and roast until golden brown and crisp, about 15-20 minutes.
Mix together mustards, ground turmeric, agave and lemon juice. Taste and adjust seasoning if needed. Add into a small bowl and set in the fridge.
Once potatoes are done, place in a bowl, serve warm with the mustard sauce on the side. These are addicting, so enjoy!