Heat oil in a pot or skillet over medium heat.

Sauté the chopped onions, minced garlic, and red bell pepper for about 1 minute.

Add the eggplant and shiitake mushrooms, and sauté for another 2 minutes.

Season with Italian seasoning, salt, and black pepper.

Pour in the tomato sauce and mix well. Let it simmer for 5 minutes.

Add the cooked macaroni pasta to the sauce and mix until well coated. Cook for 1 more minute.

Transfer the pasta mixture to a baking dish and set aside.

In a separate pan, melt the butter over medium heat.

Add the flour and whisk until smooth. Cook the roux for about 2 minutes.

Slowly pour in the milk, whisking constantly to avoid lumps.

Once the milk is fully incorporated, turn off the heat and add the cheddar and parmesan cheese. Stir until melted and smooth.

Pour the cheese sauce over the macaroni in the baking dish, spreading it evenly.

Bake in a preheated oven at 375°F (190°C) for 25 minutes, or until the cheese is golden and bubbly.

Remove from the oven and sprinkle with dried basil leaves.

Serve hot and enjoy!