Annie's Cornish Pasties - Lavender and Lovage

Ingredients

• 450g plain flour
• 115g chilled butter, cut into small cubes
• 115g chilled white vegetable fat (such as Trex, or lard)
• 1/4 teaspoon salt
• cold water to mix
• 350g beef, cut into small slivers, almost shaved but NOT minced (I use rump steak)
• 2 medium potatoes (peeled and shaved into thin slivers or very small dice)
• 1/2 large swede (peeled and shaved into thin slivers or very small dice)
• 1 medium onion (peeled and cut very finely)
• salt and black pepper
• 1 small egg (beaten )