Soak raisins in hot water for 30 minutes. Preheat the oven to 425 degrees F (220 degrees C).
In a large bowl, mix together the flour and salt.
Mix in shortening using a fork, until the entire mixture is in pea-sized pellets. Stir in yogurt, and just enough of the 1/2 cup of cold water to hold it together in a dough.
Roll out dough to a square 1/8 inch in thickness. Use a knife to cut into four 8x8 inch squares. Don't worry if they aren't perfect.
Drain the raisins, and mix with the cinnamon and chopped bananas. Spoon some of the banana mixture onto half of each square, leaving at least 1/2 inch of dough exposed at the edge to seal the edges. Fold the dough over the fruit, and pinch the edges together. Make sure that they are secure. I like to roll the excess dough up around the edges and then pinch it until it's thin again. You'll want to have about a 1/2 inch closure in the end. You can trim the edges a bit to make them more aesthetically pleasing.
Place empanadas on a baking sheet.
Whisk together 1 tablespoon of cold water and egg white; brush over the tops.
Bake for 30 minutes in the preheated oven, or until golden brown.
