Prepare the pimento cheese by combining shredded cheddar, softened cream cheese, and mayonnaise in a mixing bowl. Stir until smooth and creamy, then add diced pimentos, smoked paprika, garlic powder, onion powder, black pepper, and a pinch of salt. Mix everything well until fully incorporated, then cover and refrigerate for at least 15 minutes.
Choose a high-quality brisket, preferably USDA Prime or Choice. Trim excess fat to about ¼ inch thick.
Season the brisket with a simple salt, pepper, and garlic (SPG) rub or a brisket seasoning blend.
Preheat your smoker to 225°F (107°C) using hardwood for bold flavor.
Smoke the brisket fat-side up, maintaining a consistent temperature of 225°F–250°F.
When the brisket reaches 165°F, it may stop rising in temp (the stall). Wrap in butcher paper to push through the stall faster.
Continue smoking until the internal temperature reaches 200-205°F. Let the brisket rest for at least 1 hour.
Slice the brisket against the grain into ¼-inch thick slices.
Heat a griddle or large skillet over medium-low heat. Spread a thin layer of softened butter on the outside of each sandwich.
Place the sandwiches onto the heated pan, pressing them down gently. Cook for about 3-4 minutes on the first side, then flip and repeat.
Serve the sandwiches immediately while the cheese is hot and melty.
