Shepherds Pie with Potato Gems

My mum always made Shepherds Pie (usually with lamb) but I tried beef instead. And added potato gems which make it so easy! But you could easily add mashed potato.
Thanks for the inspo Nicole from Simple Home Edit

Ingredients:

1 onion, diced
2 celery stalks, diced
1 kg beef mince
1 tsp freshly minced garlic
Salt
½ cup tomato paste
3 tbsp plain flour
2 cups (500 ml) beef stock
⅓ cup red wine
2 tbsp Worcestershire sauce
½ tsp cracked black pepper
2 cups frozen carrots, peas, corn, bean mix
1/2 packet frozen Potato Gems
Tasty cheese, grated

Method:

Heat a large, deep, heavy-based frying pan over medium heat. Add the olive oil, onion and celery.
Cook, stirring, for 4–5 minutes, until the vegetables begin to soften.

Add the beef mince. Cook, stirring, for 4–5 minutes until browned, breaking the beef up with your spoon as you go.

Add the garlic, and salt. Continue to cook, stirring, for 1 minute.

Stir through the tomato paste and, once well combined, stir through the flour until it is dissolved.

Add the beef stock, red wine, Worcestershire sauce and pepper. Cover, reduce the heat to medium–low and simmer for 10 minutes.

Stir, remove the lid and continue cooking for 10 minutes, or until the sauce has thickened into a gravy. Add the frozen vegetables and stir through until thawed.

Turn off the heat and transfer the mixture to a baking dish (roughly 1.5 litres/6 cups). Allow the mixture to cool slightly.

Preheat oven 180.c
Place potato gems on top of pie mixture and then sprinkle with cheese.

Cook 30 mins or until gems are cooked though.