Cottage pie with cauliflower mash

Ingredients

• 2 tablespoons olive oil
• 1 large carrot, finely chopped
• 2 celery stalks, thinly sliced
• 1 large onion, finely chopped
• 500 grams beef mince
• 2 tablespoons tomato paste
• 2 cups campbell’s real beef stock
• 2 tablespoons worcestershire sauce
• 1/4 cup parsley, coarsely chopped
• 1 head cauliflower (1kg), cut into florets
• 1/3 cup cream
• 60 grams butter
• 1 cup grated tasty cheese
• mixed salad leaves to serve