01 - Preheat your oven to 375°F (190°C). Lightly grease a 9x13-inch baking dish.
02 - Boil the elbow macaroni in salted water until it reaches the al dente stage. Drain thoroughly and set aside.
03 - In a large saucepan, melt the butter over medium heat. Incorporate the flour and cook, whisking constantly, for about 1-2 minutes until faint golden.
04 - Gradually whisk in the whole milk and heavy cream. Continue to stir and cook until the mixture thickens, approximately 3-5 minutes.
05 - Reduce the heat to low. Add the shredded cheddar, Monterey Jack, softened cream cheese, garlic powder, onion powder, smoked paprika, salt, and black pepper. Stir until the cheeses are fully melted and the sauce is smooth and cohesive.
06 - Gently fold in the diced jalapeños, chopped dill pickles, and the pickle brine into the cheese sauce.
07 - Introduce the cooked macaroni to the cheese mixture and stir to ensure every piece is coated. Transfer the mac and cheese mixture into the prepared baking dish.
08 - In a separate small bowl, combine the panko breadcrumbs with the melted butter. Evenly sprinkle this mixture over the mac and cheese in the baking dish. Arrange the reserved jalapeño slices on top, and sprinkle with fresh parsley if using.
09 - Place the dish in the preheated oven and bake for 20-25 minutes, or until the top is golden brown and the sauce is bubbly. Allow to rest for 5 minutes before serving.