Liberally coat the entire brisket in the spice rub. Place it in the crock of the slow cooker fat side up and pour the broth around the edges. Place the lid on and cook, undisturbed for 10 to 12 hours. The meat should reach 190 to 200° F and shred easily. Remove from the slow cooker and rest for 30 minutes before shredding.
Make a layer of chips in a skillet or on an oven-safe pan or dish. Top with the brisket, beans, and pepper jack cheese. Place under the broiler for just a few minutes to melt the cheese.
Add the tomatoes, onion, and jalapeños. Top with the crumbled queso fresco cheese, dollops of sour cream, drizzle with the BBQ sauce, a sprinkle of chopped cilantro, and a squeeze of lime.