Traditional Welsh Shepherd's Pie

Method

1. Preheat oven to 200°C (400°F).
2. In a large pan, cook the onion, carrots, celery, and garlic until softened.
3. Add the minced beef and cook until browned.
4. Stir in mushrooms, tomato paste, and beef broth. Simmer for 20 minutes.
5. In a separate pot, boil potatoes until tender. Mash with butter, milk, salt, and pepper.
6. Transfer the meat mixture to a baking dish. Spread the mashed potatoes on top.
7. Brush with egg yolk and bake for 25-30 minutes until golden.
8. Check that the ground meat reaches 71°C (160°F) throughout before serving.