Rub the flour, butter and sugar between your thumbs and forefingers until the dough resembles bread crumbs. Add two egg yolks and one whole egg. Set the remaining egg whites aside.
Knead the dough until it forms a ball. If the dough is sticky (it should leave your hands relatively clean) add a little more flour and knead again. Cover in plastic wrap and rest in the fridge for at least 1 hour.
Peel and core the apples and dice into small cubes. Add to a saucepan, along with the nuts, sultanas, sugar and ground cinnamon. Stir until mixed and keep stirring until the sugar melts and thickens. Add the orange zest and -juice and allow to heat through. Place a lid on the saucepan, take it off the heat and allow to cool slightly while you get on with the rest.
Preheat the oven to 340 degrees F (170 degrees C). Grease a 12-cup muffin tin (or use a silicone muffin tray).
Dust your work surface and hands with flour. Make 12 small apricot-sized balls between your hands and press flat on the work surface (about 1/8"/3 mm thick). Cover the rest of the dough with plastic wrap. Line the muffin cups with the dough, working it up the sides.
Drain the apple & sultana mix in a sieve, reserving the cooking liquid for later. Add the fruit to the pastry-lined muffin cups and fill to the top, tamping down the fruit with the back of a teaspoon. With the remaining dough, shape small balls (about half the size of the previous ones) into flat disks to fit the top of the pies.
Beat the egg whites and brush the tops of the pastry sides with egg white before pressing down the 'lids'. Place in the oven and bake for 15-20 minutes.
