Place pork butt in large Dutch oven or medium-size stock pot. Add garlic, peppercorns, bay leaves and salt. Add enough cold water to cover by at least 3 inches. Bring just to a boil on high heat, quickly reduce heat to medium-low, and let simmer, partly covered, skimming any froth from the top during the first 15 to 20 minutes of cooking. A piece this size should be well-cooked but not dried out in 1 1/2 to 2 hours. Remove from stock and let cool to room temperature. When cool, pull meat into fine shreds.
Strain and degrease the stock. It will be easier to remove fat when thoroughly chilled.
Can be kept, tightly covered, 2 days in the refrigerator, if de-greased at once, up to 1 week if you leave the top layer of fat on it until ready to use. The stock also freezes well.
In a mixing bowl, combine the shredded pork with the red chile sauce.
Place 10 pounds of masa in a large plastic mixing bowl. Mix 1/4 cup water with baking powder in a cup held over the bowl with the dry masa until it fizzes, then pour mixture evenly over masa. Add 1/4 cup salt and work masa with hands to mix evenly. Melt 4 cups vegetable shortening in a large saucepan and allow to cool. Pour evenly over masa and knead masa with hands again. When it starts to feel thick and compact (like fudge) it’s ready. Pat down in bowl and set aside.
In a large saucepan, boil chiles and tomatoes together for about 10 minutes or until softened. Drain the chiles and tomatoes and reserve the water (stock.) Set stock aside. Rinse seeds out of boiled chiles at sink. Grind garlic, 2 teaspoons salt and whole cumin with mortar and pestle. Put chiles, tomatoes, 3 additional tablespoons salt and ground ingredients together in blender and blend well. Add 2 cups of the reserved water (stock.)
In a heavy, medium-size saucepan, heat 2 tablespoons vegetable oil over medium-high heat until rippling. Add flour, stirring constantly until golden. Add strained chile puree to the pan and reduce the heat to low. It will splatter, so be careful. Cook over low heat, stirring often, until the raw taste is gone and the flavor of the chiles has mellowed, about 10 minutes.
In a mixing bowl, combine the shredded pork with the chile sauce.
To assemble the tamales, soak dried corn husks in warm water for about 1 hour until soft. Spread masa mixture evenly onto husk using a wooden spoon. Fill with about 2 tablespoons pork mixture and top with 1 green olive, 1 slice of potato and 1 carrot stick. Fold and tie ends with pieces of corn husk. Steam for 1 and 1/2 hours.
To steam: To make a steamer, place a metal rack (such as a cooling rack) in the bottom of a large stock pot or canner. Water level should be below the rack. Lay extra corn husks over rack. Stand the tamales on the folded edge in the steamer (the open edge with be facing upward). First fill the bottom of the steamer, then start stacking tamales on top of one another. Place any extra husks on top of tamales, cover with pot lid and steam for 1 to 1 1/2 hours. Replenish boiling water if necessary during steaming, time. The tamales are done when the husk peels away easily from the filling.