Soak the raw cashews in very hot water for 15 minutes and drain. Blend with 3/4 cup hot water, nutritional yeast, dijon mustard, lemon juice, garlic powder, onion powder and salt until completely smooth.
Pour the cheese sauce into a small saucepan and warm over low heat, stirring occasionally, until thick and pourable like melted provolone.
Heat 1 tablespoon of the olive oil in a large skillet over medium high heat. Cook the onion and bell pepper for 6-7 minutes until soft and lightly caramelized, then transfer to a plate.
Add the remaining olive oil to the hot skillet and sear the shaved beef for 2-3 minutes, breaking it apart, just until no longer pink. Season with the salt and black pepper.
Return the onions and peppers to the skillet and toss everything together for 1 minute.
Split and lightly toast the hoagie rolls.
Pile the steak mixture into the rolls and drizzle generously with the warm cheese sauce. Serve immediately while everything is hot and melty.