Original Flat Sandwich Bun

This bun has incredible holding power that assures you’ll never worry about the integrity of your sandwich.

Product sheet (pdf)

Poblano prime rib


  • 6–8 Boulart® Original flat sandwich buns
  • 1 x 3 lb piece prime rib
  • 1 bunch rosemary, picked and finely chopped
  • 1 cup Dijon mustard
  • 6 poblano peppers
  • 4 cups apple cider vinegar
  • 1 cup sugar
  • 4 cloves garlic, thinly sliced
  • 2 bay leaves
  • Kosher salt
  • Pepper
  • ½ a lemon



  • ½ bunch parsley, roughly chopped
  • 1 bunch mint, roughly chopped
  • ½ red onion, finely chopped
  • ¼ cup apple cider vinegar
  • Extra virgin olive oil



  • 4 cups mayonnaise
  • 12 cloves roasted garlic, mashed with a fork


  1. Pre-heat oven to 350 °F (190 °C). Season prime rib liberally with salt, black pepper and mixture of rosemary and mustard. Place in oven on a tray or baking sheet.
  2. Deseed peppers and slice half an inch thick. In a large pot, bring other ingredients to a boil, seasoning with salt. Add peppers and cover with lid, stirring every few minutes until they are submerged. Turn off heat and allow peppers to cool.
  3. To make salsa, mix red onion, vinegar and salt (to taste) in a bowl and let sit for 10 min. Stir in parsley, mint and olive oil to coat the herbs and adjust seasoning with salt and lemon juice.
  4. To make aioli, combine garlic, mayo and salt, to taste.
  5. Once roast has an internal temperature of 120 °F (49 °C) remove it from oven. Split warm buns open and spoon aioli on both sides. Pile three slices of beef on the bottom half, add some peppers and salsa. Top with the other half of the bun.