Mustard Vinaigrette Dressing

Our favourite mustard vinaigrette dressing. Perfect for radicchio or iceberg wedges and avocado. And there's a video. Mustard Vinaigrette Dressing 2/3 cup extra virgin olive oil ((or hazelnut oil for a lovely change))1/3 cup best-quality red wine vinegar2 tsp Dijon mustard1/2 - 1 tsp sea salt flakes1/4 tsp freshly ground...