Pour the gallon of whole milk into a large pot and heat it over medium heat, stirring occasionally to prevent scorching. Heat the milk to 86°F.
Sprinkle the packet of mesophilic culture over the surface of the milk and stir it in using an up-and-down motion. Cover the pot and let the milk sit for 30 minutes.
In a small bowl, mix the 1/4 teaspoon of liquid rennet with 1/4 cup of non-chlorinated water. Pour the mixture into the pot of milk and stir it in using the same up-and-down motion. Cover the pot and let the milk sit for 45 minutes, undisturbed.
After 45 minutes, the milk should have formed into a solid gel-like mass. Use a long knife to cut the curds into 1/2 inch cubes. Let the curds sit undisturbed for 5 minutes.
Heat the curds over medium heat, stirring occasionally, to 102°F. This should take about 20 minutes.
Once the curds have reached 102°F, use a slotted spoon to transfer them into a cheesecloth-lined colander. Gently press the curds to remove as much whey as possible. Then, tie the cheesecloth into a knot and hang it to drain for 1-2 hours.
Once the curds have drained, transfer them to a mixing bowl. Add the kosher salt, chopped pickled jalapenos, red pepper flakes, and garlic powder. Mix well.
Press the curd mixture into a cheese mold or shape it into a ball using your hands. Let the cheese rest at room temperature for 12-24 hours, flipping it over halfway through.
If you'd like to wax your cheese, melt the cheese wax in a double boiler over medium heat. Dip the cheese into the wax and let it cool completely. Repeat the dipping process 2-3 times to ensure the cheese is fully coated.
Once your cheese has been formed and waxed (if desired), let it age in a cool, dry place for 2-4 weeks. During this time, the cheese will develop its flavor and texture.