In a bowl, whisk together the red wine vinegar, soy sauce/tamari, spice rub, and olive oil.
Brush onto the London broil equally on both sides, cover, chill, and allow to marinate for 3-24 hours.
Allow to come to room temperate before cooking.
Wipe mushrooms cleans with a paper towel and trim stems if necessary.
In a sauté pan over medium heat, add the olive oil to the hot pan.
Place the mushrooms cap side down and do not disturb until they have browned to golden, 5-7 minutes.
Stir and allow to cook on all sides, about 5 minutes.
Add the butter, and continue cooking for 5 minutes more or until mushrooms are deep golden brown all over.
Add the salt, pepper, garlic, and thyme, mix well.
Add the wine, pull up all the stuck on bits at the bottom, and continue to stir until all the wine has been absorbed.
When ready to assemble, quarter-slice the mushrooms.
In a heavy-bottom saucepan over medium heat, add the cream and the blue cheese, stir constantly as it warms to a low simmer/bubbles.
Add the Worcestershire sauce, onion powder, and pepper, return to a low simmer, stirring constantly.
Taste for seasoning, add salt if needed.
Return to simmering until the sauce reduces and thickens.
There will still be some small chunks of blue cheese in the sauce.
Cook fries according to package directions.
Remove from fridge and allow to get to room temperature before grilling.
Heat grill to hot, once hot, reduce the flames to low and keep steady at 400°F.
Place on the grill, let cook for 4 minutes, then rotate the steak 90° on the same side and resume cooking an addition 3 minutes.
Flip and cook for 3 minutes to medium rare; cook longer for a more well done steak.
Allow to rest for at least 5 minutes before slicing.
On a platter, arrange the fries.
Add the sliced beef.
Sprinkle the mushrooms over beef and fries.
Drizzle the creamy blue cheese sauce over the top, as much as desired.
Sprinkle the chives and the Stubb's All-Natural Steak Spice Rub over the top.