Twice baked potato with mushrooms, blue cheese and balsamic onions recipe

Ingredients

• 4 baking potatoes
• 4 small red onions, peeled and left whole
• 1 tbsp olive oil
• 60g butter
• 300g chestnut mushrooms (field or button would also work), roughly chopped
• 1 large garlic clove, finely chopped
• 100g soft blue cheese like Saint Agur or Gorgonzola, crumbled
• 1 tbsp cream cheese
• 1 tbsp balsamic vinegar
• 1 small bunch of parsley, roughly chopped