Beef shepherd's pie

Name: Beef shepherd's pie
Prep time: 25 min
Cook time: 45 min
Total time: 1 h 10 min
Cuisine: European, British
Ingredients: 18.20 gm olive oil; 1 brown onion, chopped; 1 large carrot, cut into 1cm pieces; 1 celery stick, cut into 1cm pieces; 2 garlic cloves, crushed; 1kg 3 Star Beef Mince; 44.40 gm tomato paste; 400g can crushed tomatoes; 24.40 gm Worcestershire sauce; 185ml beef stock; 120g pea; 3.5 x 350g Kitchen Creme Royal potato mash; 40g 1/2 cup grated tasty cheese; Mixed salad leaves, to serve