Add 1 tablespoon of the olive oil to a sauté pan over medium high heat. Add the diced celery, carrots, onion, and bell pepper, and sauté for a few minutes until soft and fragrant. Add the minced garlic and stir to combine.

Add the tomato paste, diced tomatoes, vegetable broth, spices, brown sugar, salt, and pepper to the pan. Mix to combine.

Add the dry lentils and mix to incorporate them. Bring the mixture to a low boil and then let simmer for about 10-15 minutes, until the lentils are cooked through and the mixture is thick, stirring occasionally. All of the liquid should be soaked up or evaporated. If there is no more liquid and the lentils aren’t fully cooked, add 1/4 cup at a time more of the vegetable broth. Squeeze the lime juice over the mixture and stir gently.

Transfer the lentil mixture to a large bowl and set aside. Wipe the pan clean and add olive oil for cooking the tacos.

Once the oil is hot, lay the tortilla on the pan. Add 1 heaping tablespoon of the lentil mixture to one side of the tortilla. Top with 2 teaspoons each of shredded mozzarella. Fold the taco in half, using the back of the spatula to push and hold the tortilla down. Let cook for a few minutes on each side, until the tortilla is crisp and golden and the cheese has melted.

You can likely cook 2-3 tacos at a time in the pan. After cooking, transfer the tacos to a plate and add more oil as needed.