Heat the 1 tbsp olive oil in a large Skillet over medium-high heat. Add the diced 1 yellow onion finely diced and 1 green bell pepper finely diced and cook, stirring occasionally, until softened — about 5 minutes. Add the minced 3 cloves garlic minced and cook for 1 more minute until fragrant.

Add the 1 ½ lb ground beef 80/20 recommended to the Skillet. Break it up thoroughly with a Wooden Spoon and cook until no pink remains, about 6–8 minutes. Carefully drain off any excess fat, leaving just a thin film in the pan for flavor.

While the 1 ½ lb ground beef 80/20 recommended cooks, whisk together the 1 cup ketchup, 2 tbsp tomato paste, 1 tbsp Worcestershire sauce, 1 tbsp yellow mustard, 2 tbsp brown sugar packed, 1 tbsp apple cider vinegar, ½ cup water, 3 cloves garlic minced, ½ tsp onion powder, ½ tsp kosher salt plus more, and ¼ tsp black pepper freshly ground in a Mixing Bowl or large Measuring Cups until smooth.

Pull the brisket from the Refrigerator 30 to 60 minutes before cooking to let it approach room temperature. Trim hard fat down to about a quarter inch. Apply your dry rub or salt-and-pepper blend evenly over the whole surface, pressing it in firmly. Soak Wood Chips in water for at least 30 minutes if your Smoker uses chips, or prep wood chunks and pellets per your smoker's directions. Empty the drip tray before you start. Set aside unwaxed Butcher Paper or heavy-duty Aluminum Foil for wrapping later in the cook.

Preheat your Smoker to 225–250°F and verify the temperature with a standalone Meat Thermometer. Add Wood Chips, chunks, or pellets per your smoker's instructions. Place the brisket fat side up with the point end toward the heat source. Close the smoker and avoid opening it often. Check wood and adjust vents every 45 minutes to hold 225–250°F. Rotate the brisket every 3 hours and flip if one side colors faster. Smoke uncovered until the internal temperature hits 165°F and a dark bark has formed, about 5 to 8 hours. Wrap tightly in Butcher Paper or Aluminum Foil, return to the smoker, and continue until an Instant-Read Thermometer reads 195–203°F and the meat is very tender but not falling apart, roughly 4 to 5 more hours. Total cook time is typically 8 to 12 hours. Use internal temperature and texture as your doneness cues, not the clock alone.

While the filling simmers, toast the 6 hamburger buns brioche or potato buns preferred. Melt 2 tbsp unsalted butter for toasting buns in the Skillet (or use a separate Skillet) over medium heat and toast the cut sides of the 6 hamburger buns brioche or potato buns preferred until golden, about 2 minutes. Alternatively, toast them under the Broiler.

Spoon a generous heap of the sloppy joe filling onto the bottom half of each toasted 6 hamburger buns brioche or potato buns preferred. Top with the other 6 hamburger buns brioche or potato buns preferred half and serve immediately with napkins — it's supposed to be messy!