Step 1

Preheat the oven to 300 degrees F.

Step 2

Start the brisket: Heat the olive oil in a large Dutch oven over medium-high heat. Sprinkle the brisket with the House Seasoning. Place the brisket, fat-side down, in the hot Dutch oven and brown until a deep golden crust forms, 5 to 7 minutes. Turn the brisket over and brown on the other side, another 5 minutes. Remove the brisket from the Dutch oven. Add the onions and bell pepper to the drippings in the Dutch oven and stir until well coated in oil. Add the beef broth and bay leaf and bring to a boil. Return the brisket to the Dutch oven. Cover and place in the oven. Bake for 3 hours.

Step 3

Meanwhile, make the sloppy joe sauce. Combine the diced tomatoes, ketchup, brown sugar, molasses, apple cider vinegar, garlic powder, mustard, paprika and cayenne pepper in a medium saucepan. Bring to a boil. Reduce the heat and simmer over medium-low until slightly thickened and reduced by one-fourth, about 30 minutes.

Step 4

After the brisket has baked for 3 hours, pour 2 cups of the sauce over the brisket. Cover the Dutch oven and continue baking the brisket until tender, 30 minutes longer. (Use a knife to test the tenderness of the brisket. It should pierce the brisket very smoothly, with no pushback.) Shred the meat using two forks and stir in 1 more cup of sauce. Season with salt and pepper.

Step 5

During the last 30 minutes, make the fried onions: Pour oil halfway up the sides of a large cast-iron skillet and heat to 350 degrees F.

Step 6

Place the onion in the buttermilk in a small bowl. Place the flour in a shallow baking dish and season with salt and pepper. Working with a few onions at a time, dredge them in the flour, shaking to remove any excess flour. Add to the hot oil and fry until golden brown and crispy, about 4 minutes. Remove the onions to a baking sheet with a wire rack and sprinkle with the House Seasoning while still hot. Repeat with the remaining onions and set aside.

Step 7

To assemble the sandwiches, spoon some of the brisket on the hamburger bun bottoms. Top with the fried onions, pickles and bun tops.

Step 8

Stir together the garlic and onion powders, paprika, salt and pepper in a small bowl. Store in an airtight container.