If you're daunted by working with this large volume, divide recipe in half. Have your local butcher grind the pork loin at least 2-3 times. Add the ground pork, potato starch, salt, sugar, fish sauce in large mixing bowl. Add about 6 cups of water to the mixture, save the remaining 1 cup. To that, dissolve the Alsa baking powder and combine with the pork mixture and mix well. Cover tightly with plastic wrap and refrigerate over night, and not more than one day.
The following day, you will need to combine cinnamon to the mixture and bake. We also process the mixture with a food processor one more time to make sure it has a smooth consistency. Preheat the oven to 350 degrees and grease cookie sheets with Pam or neutral oil. Working in batches (depending on the capacity of your food processor .ie 8 cups, 14 cups etc and avoid overloading your food processor) Add approximately 1 ts of cinnamon for every 2 cups of pork mixture and give a few quick pulses to thoroughly combine the cinnamon. At this point, take a teaspoon or so of the mixture and microwave for about 30s and taste. Adjust seasoning such as cinnamon or salt if needed. Continue until all the ground pork has been processed with cinnamon.
Using a wet rubber spatula, spoon onto the greased cookie sheet from edge to edge and make an even layer of pork paste about 3/4" thick. Use multiple baking sheets as necessary. Don't worry about going up to the edges because when it bakes, it will pull away. When baking sheet is covered entirely, use a wet spatula or wet hand, smooth out the top layer of the pork mixture. Bake at 350 degrees. AFter 10 or 15 minutes, the top layer of the pork will start to form a dull light brown skin. At this point, open the oven and carefully pierce the surface of the pork randomly with a fork to allow some of the trapped air to escape. Continue to cook until it has a golden brown crust. Remove and allow to cool before slicing.