Cook the mushrooms with 1 tablespoon oil in a large skillet on medium heat.
After 2 minutes, add in onion and cook 3 minutes. Then add in bell peppers and carrots, and stir frequently. If the oil has been used up, add the other tablespoon.
Add tomato paste and mix well into the vegetables. Add tomato sauce.
Add tamari and worcestershire sauce, then the ketchup.
Do a taste test. You may add a little more tamari, worcestershire or ketchup depending on your taste. Wait until tasting to salt and pepper your food.
Pile the mixture onto buns or bread.
Note: if you use beef crumbles, only use half of the mushrooms.
Note: this recipe can be converted to oil free, using water to saute all vegetables except the mushrooms; after the vegetables are softened, then add mushrooms. Follow recipe from that point.

8 oz mushrooms, finely diced
1/2 onions, diced
1/2 green bell pepper, sliced
1 medium carrot, diced into small cubes
1/2 small can tomato sauce
1/2 small can tomato paste
3 tablespoon tamari sauce
1/4 cup worcestershire sauce
1/4 cup ketchup
optional:
2 tablespoon oil
1/2 bag vegan beef crumbles
buns or bread