Cut the potatoes into wedges, then place in a large bowl. Scatter the coating mix over the potatoes, and toss well to coat.
Put 2 Tbsp of the Beef Marrow Cooking Blend on a non-stick baking tray. Place in the oven for 5 minutes or until the oil has just melted. Carefully place the wedges onto the heated baking tray and place in the oven. Bake for 25-35 minutes, turning halfway through, until golden brown and tender.
To make the dip, combine the sour cream, vinegar and chives in a bowl. Season to taste.
Serve the hot wedges alongside the dip and enjoy immediately, garnished with chopped chives.