Roasted potato salad with shallots and sour cream

Ingredients

• 900g Maris Piper potatoes
• 3 tbsp olive oil
• 1.5 tsp salt
• 1 tsp freshly ground black pepper
• 4 medium echalion shallots, thinly sliced
• 2 cloves of garlic, finely chopped
• 80g sour cream
• 1 tsp Dijon mustard
• 1 tsp red wine vinegar
• 2 tbsp flat leaf parsley, chopped