Concentrate the Salsa Pectins - Heat your 12-inch cast-iron skillet over medium heat. Add the chopped tomatillos, diced white onion, minced jalapeños, and garlic. Pour in the 1/2 cup of chicken stock and salt. Simmer uncovered for 10-12 minutes, stirring occasionally, until the tomatillos collapse completely into a thick, chunky green sauce and half the water content evaporates. Stir in the chopped cilantro, then scrape the sauce out into a bowl and set aside.

Synthesize the Protein Core - In a medium bowl, combine the 3 cups of shredded chicken breast with the ground cumin, smoked paprika, garlic powder, and 2 tablespoons of the warm green salsa you just prepared. Toss well to distribute the spices evenly through the meat fibers.

Apply the Amylose Starch Shield - Clean and dry your box grater. Coarsely shred your block of cheddar cheese into a bowl. Immediately sprinkle the 1 teaspoon of cornstarch over the fresh shreds. Toss the cheese thoroughly with your fingers for 30 seconds until every strand has a thin, dry coating. This prevents the proteins from clumping together tightly when they touch the acid in the sauce.

Pliable Tortilla Modification - Wipe out your cast-iron skillet and brush it with a light coat of avocado oil over medium-high heat. Sear each corn tortilla for 15 seconds per side until warm, soft, and slightly charred. Transfer them to a clean kitchen towel to keep them pliable. This gelatinizes the corn starches so the tortillas roll without tearing.

Assemble the Lamination Matrix - Spread 1/2 cup of the green salsa verde over the bottom of your warm cast-iron skillet. Take a soft tortilla, pack 1/8 of your seasoned chicken mixture across the center, and roll it up tightly. Place it seam-side down into the skillet. Repeat with the remaining 7 tortillas, packing them closely side-by-side to prevent them from opening up.

Execute Radiant Fusion Melting - Pour the remaining green salsa verde evenly over the tops of the rolled enchiladas. Scatter the starch-coated shredded cheddar cheese in an even layer completely covering the surface. Turn on your oven's broiler element to high. Slide the entire skillet onto the top oven rack directly under the broiler. Broil for 3 to 4 minutes until the cheese is melted, smooth, and spotted with golden brown. Remove from heat and rest for 5 minutes before serving to let the cheese emulsion stabilize.