Blenditarian Quick Sloppy Joes with Pickled Cabbage

In a large saute pan, cook the mushrooms in the olive oil with a pinch of salt and pepper over medium high heat, until the mushrooms are softened and excess liquid has evaporated, about 5-6 minutes. Add the chopped onion, and cook until the onion softens, about 4 more minutes.  Add the ground beef and cook until no longer pink, breaking up the meat with a wooden spoon, about 5 more minutes.  Add the garlic, dried mustard and chili powder and cook for another 5 minutes stirring frequently.   Add the ketchup and barbecue sauce, and cook until well-blended and fragrant, about 3 minutes, stirring frequently.  While meat is cooking, place the cabbage, vinegar and a pinch of salt in a medium bowl and toss to coat.  Let the cabbage sit at least five minutes, or up to 24 hours (refrigerate if setting sit longer than an hour). To serve:  Spoon some of the blenditarian mixture on the bottom of the bun and a heaping spoonful of the pickled cabbage on the top of the bun.  (NOTE: The crunch cabbage is incredible!  But if you forego the cabbage, stir a teaspoon or two of vinegar into the sloppy joe mixture to balance the sweetness with acidity.)