Step 1

Heat oil in large saucepan over medium heat. Add onion, carrot and celery. Cook, stirring, for 3 to 4 minutes or until onion has softened. Add mince. Cook, stirring with a wooden spoon to break up mince, for 5 minutes or until browned.

Step 2

Add worcestershire sauce, tomato paste, tomato and herbs. Bring to the boil. Reduce heat to low. Simmer for 20 to 25 minutes or until thickened. Stir in peas. Preheat oven to 180°C/160°C fan-forced.

Step 3

Meanwhile, cook potato in a saucepan of boiling water for 8 minutes or until just tender. Drain. Return to pan. Add milk and butter. Mash until smooth. Spoon beef mixture into a 5cm-deep, 6 cup-capacity ovenproof dish. Top with potato mixture. Sprinkle with cheese. Bake for 30 to 35 minutes or until golden. Serve.