- Heat the oil in a saucepan over medium-high heat. Stir in onion, celery, and zucchini. Fry until vegetables are tender and liquid from zucchini has evaporated.
- Add tomatoes, chili sauce, tomato paste, sugar, and hot pepper flakes. Season with salt and pepper. Reduce heat to medium-low and simmer uncovered for about 25 minutes or until sauce has thickened. Add the lentils and herbs. Set aside.
- Preheat broiler.
- Brush eggplant slices lightly with oil. Add salt and pepper to taste. Place on a baking sheet and broil for about to 4 minutes per side. Repeat as needed. Set aside.
- Preheat oven to190°C (375°F).
- Cover the bottom of a lasagna dish measuring approximately 20cm x 28cm x 5cm (8 in. x 11 in. x 2 in.), with a thin layer of tomato sauce. Cover with a layer of grilled eggplant. Pour in half the tomato sauce, then cover with another layer of grilled eggplant. Spread the ricotta cheese. Salt and pepper to taste. Cover with another layer of eggplant. Pour in the rest of the tomato sauce, then cover with a final layer of eggplant. Spread the grated cheese mix over top.
- Cook in oven for 25 minutes or until cheese is golden and sauce boils.
Serve lentil and vegetable tomato sauce on your favourite pastas for delicious