3/4 cup California walnuts
1-pound Portobello mushrooms, gills and stems removed
2 tablespoons canola oil
1 medium onion, chopped
1 green bell pepper, chopped
4 cloves garlic, minced
1-1/2 cups ketchup
2 tablespoons brown sugar
1/2 teaspoon dry mustard
1/2 teaspoon cayenne pepper
1 tablespoon tomato paste
1 tablespoon Worcestershire sauce (or vegan Worcestershire)
1 tablespoon apple cider vinegar
1/2 teaspoon salt
8 potato buns, toasted
Pulse the walnuts and mushrooms in a food processor in batches until it breaks down and resembles a ground beef texture.
Heat oil in a large skillet over medium-high heat. Add the onions, bell pepper, and minced garlic, and cook for 5 minutes or until the veggies soften.
Add the walnuts/mushroom mixture to the skillet, stir so everything is well combined and let cook for 5 minutes.
In a small bowl, combine ketchup, brown sugar, dry mustard, cayenne pepper, tomato paste, Worcestershire sauce, and apple cider vinegar, then add to the skillet. Stir everything together and let simmer for 5 minutes. Adjust with salt to taste.
Serve the prepared sloppy joe mix on top of toasted buns. Serve immediately while still warm.