Heat the oven to 425°F (220°C). Start the cashew soak. Arrange the eggplant slices on baking sheets, brush with their measured oil and season with salt and pepper. Roast for 20–25 minutes, turning once, until tender with golden edges. Work in a single layer so the slices roast evenly.

While the eggplant roasts, heat the sauce portion of oil in a saucepan. Soften the shallot, then add the minced garlic. Stir in the tomatoes, tomato paste, pepper flakes, Italian seasoning, balsamic vinegar, lemon zest, measured salt and pepper. Simmer gently for 10–12 minutes until lightly thickened.

Drain the soaked cashews. Blend them with the nutritional yeast, garlic, juice of the listed lemon portion, measured salt, milk and optional miso until smooth. Scrape down as needed. The cream should spread easily; add a small splash of water only if needed.

Lower the oven to 400°F (200°C). Spoon a little tomato sauce into a roughly 2-quart baking dish. Layer in the eggplant, remaining sauce and cashew cream, repeating as space allows. Mix the breadcrumbs with their measured oil and scatter over the top.

Bake for 20–25 minutes, until the sauce is bubbling around the edges and the crumb topping is golden. Check the top near the end so it does not scorch.

Let the bake rest for 10 minutes before serving. Add the optional basil. Expect tender, spoonable layers rather than a firm, sharply sliced casserole.