In a large skillet heat 1 teaspoon oil and cook beef and pork, stirring occasionally, until browned, about 5 to 6 minutes.
Add onions, bell peppers, celery, salt, cayenne and black pepper. Cook, stirring often, until the vegetables are wilted, about 10 to 12 minutres. Add the garlic and cook for 2 to 3 minutes.
Dissolve the flour in the water and add to the meat mixture. Stir until the mixture thickens slightly, about 3 minutes. Remove from the heat and add green onions. Mix well and let cool.
In a mixing bowl, sift together flour, salt and baking powder. Cut in the shortening until mixture resembles coarse meal. In a small bowl, beat the egg with the milk. Gradually add the egg mixture to the flour mixture, working it to make a thick dough.
Pinch off a medium size ball of dough. Roll out ball of dough on lightly floured surface until you get approximately 5 inch cirlce. Place about 1/4 cup of meat filling in the center of each round and brush edges lightly with egg wash. Fold edges together and crimp closed with a fork.
Heat oil in a deep pot or electric deep-fryer to 360 degrees. Fry the pies, in batches, until golden. Drain on paper towels and serve immediately.
Instructions for Cajun Tartar Sauce:.
Place the egg, garlic, lemon juice, parsley and green onions in a food processor and process for about 15 seconds until pureed. With the processor running, pour the oil through the feed tube in a steady stream. Add the cayenne, mustard and salt.