Potato Salad

Ingredients

• 800g (maris pipers)
• 2 tsp wholegrain mustard
• 2 tbsp white wine vinegar
• 4 tbsp olive oil
• 1 onion, finely chopped
• 3 tbsp mayonnaise
• 2 tbsp sour cream
• 1 tbsp horseradish sauce
• 1 tsp lemon juice
• 2 spring onions, finely sliced
• Handful of crispy fried onions