Start by cutting the the chicken breast horizontally. Once you have done this, cut each piece in half. Place the chicken, and buttermilk brine ingredients in a large bowl. Ensure that all ingredients are mixed well together. Cover, and marinate for at least to 30 minutes or up to 2 hours in refrigerator if you can. Next place chicken batter ingredients into a food storage bag (such as a Ziploc bag), and set aside.
When ready to make the chicken and biscuits, preheat oven to 450 degrees. Pour cooking oil into the frying pan or deep fryer. Let grease temperature reach 340 degrees when checked with a candy/fat thermometer.
Remove chicken from refrigerator. Remove each piece of chicken and dredge the chicken piece in the flour mixture. After each piece of chicken is coated with flour, place the floured chicken pieces on a wire rack and let the chicken sit for at least five minutes. (This helps the batter adhere to the chicken). The chicken can sit while you make the biscuits.
Start making biscuits by mixing dry ingredients together in large bowl. Then, add the shortening and butter into the dry ingredients. Using a pastry blender or a fork and, cut the butter into the dry ingredients until the flour is pea-sized crumbles. Then, add the cheese, and jalapenos. Mix well. Drizzle in the buttermilk and stir just until a moist, dough comes together.
Dust your work surface with flour. Scrape the dough onto the surface and dust the top with more flour. With floured hands, pat the dough into a circle 1 inch thick.
Mold the scraps into a ball, pat it into a 1-inch-thick circle, and cut out more biscuits. Keep doing this until you have 6 biscuits.
Place the biscuits on the prepared baking sheet, placing them close together (I usually use a baking pan lined with parchment paper). Brush the top of the biscuits with additional melted butter. Place the biscuits in the oven and bake for 15 to 16 minutes. To get a nice golden brown on the top of the biscuits, use the broil temperature setting for about 1 minute or so. Remove the biscuits from oven, and set aside.
Once the oil is hot, Fry the chicken breasts until they are cooked through and golden brown. Cook the chicken for about 6 to 8 minutes, and turn the chicken halfway through. Make sure the chicken's temperature reaches 155°F when checked with a kitchen thermometer. Note: when you remove the chicken from the cooking oil, the temp will rise to 165°F as it rests. Drain the cooked chicken on a clean wire rack. (Note: this can be done while the biscuits cook.)
Once the chicken has drained. Split the biscuits in half, and place a chicken piece between each biscuit. Serve immediately.