Using a deli slicer, shave the beef as thin as is safely possible.
Steam the Beef
Preheat the oven to 300 degrees
Divide the beef into 4 equal portions and wrap in foil.
Pour the stock evenly into each packet.
Place the packets on a baking sheet and put in the oven for 15-20 minutes, until the beef is piping hot.
Make the Ooomami Mayo
Meanwhile, make the mayo by whisking the mayo, GirlCarnivore Ooomami blend, and horseradish in a bowl until thoroughly combined.
Make the Cheese Sauce
In a pan over medium-low heat, whisk the cream with the gorgonzola and Monterey jack cheese.
Add in the Ooomami and White Tux spice blends and whisk until thoroughly combined.
Allow the sauce to thicken over low heat, 3 to 5 minutes.
Remove from heat and whisk in the chives.
Assemble the Pit Beef Sandwich
Slather the buns with the Ooomami Mayo.
Top each bun with 1 packet of the foil wrapped heated beef.
Add sliced onions on top and drizzle with cheese sauce.
Top with remaining bun half and serve immediately.
This recipe uses leftover shaved beef for the best results. I do not recommend deli beef for this recipe. You can substitute blue cheese for gorgonzola if you prefer or omit it altogether and replace with a less fragrant melting cheese if desired. If you don't have a deli slicer at home, chill the beef and use a well-sharpened knife for the best chance at super thin slices.
To Make Foil Wrapped Pit Beef Sandwiches for Camping:
Follow the instructions to make these sandwiches, wrapping them in foil and cooking them over your campfire grate on the cooler side of a dual zone fire. until heated through. This recipe would also work in an RV oven. For the cheese sauce, use a cast iron or other camping pan to whisk the cheese sauce over indirect heat to prevent scorching or over a camp stove set to medium low.