Start by gathering all your ingredients. Preheat your oven to 200°C (about 400°F). While it warms, slice the aubergines lengthwise. I generally like them about 1cm thick for a tender roast. Then, sprinkle some salt on them and let them sit for 15 minutes. This will draw out excess moisture and bitterness.

Pat the aubergine slices dry, then drizzle with olive oil. Sprinkle on smoked chili flakes. Lay them flat on a baking sheet. Roast in the oven for about 25 minutes until soft and golden. The aroma will fill your kitchen like a warm hug.

In a pan, heat some more olive oil. Add finely chopped red onions and roasted garlic, cooking over medium heat. Let them soften for about 5-7 minutes; this is where the flavor begins to build! Then add in the fresh rosemary, stirring it in until fragrant.

Toss in the fire-roasted plum tomatoes and sun-dried tomatoes with your sautéed onion mix. Add balsamic vinegar and season with salt and pepper. Allow it to simmer for at least 10 minutes. This sauce is where the magic happens.

In a large baking dish, start building your lasagne. Begin with a layer of the tomato sauce, then a layer of aubergine. Next, place a layer of spinach lasagna sheets, followed by some of the cheese. Repeat until you run out of ingredients, making sure to finish with cheese on top for that golden crust.

Cover the dish with foil and bake in the oven for about 30 minutes. After that, uncover and cook for an additional 15-20 minutes, until the cheese is bubbling and golden. Let it cool for a few minutes before serving.