Try first roasted tomato sauce.

1 cup(s)green lentils
1 tablespoon olive oil
1 medium yellow onion diced
1 medium green or red bell pepper diced
2 clove(s) minced garlic
3 tablespoon chili powder
2 teaspoon oregano
1/2 teaspoon salt
1 can tomato sauce no salt added (8 oz)
1/8 cup tomato paste
3 tablespoon maple syrup or brown sugar
1 tablespoon mustard
1 tablespoon apple cider vinegar
4 whole rolls

1 cup (s)green lentils 1 tablespoon olive oil 1 medium yellow onion diced 1 medium green or red bell pepper diced 2 clove(s) minced garlic 3 tablespoon chili powder 2 teaspoon oregano 1/2 teaspoon salt 1 can tomato sauce no salt added (8 oz) 1/8 cup tomato paste 3 tablespoon maple syrup or brown sugar 1 tablespoon mustard 1 tablespoon apple cider vinegar 4 whole rolls

Combine the lentils and 4 cups water in a large saucepan. Cover the pan and bring the water to a boil. Reduce the heat to low and simmer for about 25 minutes, until the lentils are tender. Drain and set aside.

Heat the olive oil in a medium pot over medium-high heat. Add the onion and peppers and sauté until softened, about 7 minutes. Add the garlic and sauté for 1 minute. Add the cooked lentils, chili powder, oregano and salt.

Add the tomato sauce and tomato paste and mix well. Reduce the heat to low and simmer for 10 minutes. Add the maple syrup, mustard, and apple cider vinegar and heat through.

Turn off the heat and let the lentil mixture sit for about 10 minutes. Spoon the mixture over toasted buns if desired.