Soak cashews — Place raw cashews in warm water and soak 30–60 minutes (or 15–20 minutes in hot water if short on time). Drain and rinse before blending.
Prepare zucchini sheets — Use a mandoline, vegetable peeler, or sharp knife to slice zucchini lengthwise into long, thin sheets (~1–2 mm). Salt lightly and let sit in a colander 10–15 minutes to draw out moisture if zucchini are watery; blot dry.
Make the raw marinara — In a high-speed blender combine chopped fresh tomatoes, soaked sun-dried tomatoes, red bell pepper, garlic, olive oil (or water), vinegar, salt, pepper, oregano (or basil), and lemon juice. Pulse to a chunky-smooth sauce — avoid over-pureeing. If too watery, strain briefly to achieve a spreadable consistency. Taste and adjust salt/acidity.
Make the cashew “ricotta” — In a food processor, add soaked cashews, lemon juice, 2 tbsp water, nutritional yeast, garlic, salt, and apple cider vinegar. Process until smooth and spreadable; scrape sides and add water 1 tsp at a time if needed. Stir in chopped basil or parsley. Aim for a creamy ricotta-like texture (not soupy).
(Optional) Make the pesto — In a small blender/processor, pulse basil, nuts/seeds, garlic, and nutritional yeast. Stream in olive oil (or water) until a thick, spoonable pesto forms. Season to taste.
Assemble the lasagne — Lightly oil or spread a thin layer of marinara on the bottom of a 9×9-inch (or similar) dish. Layer in this order and repeat:
1 zucchini sheet (trimmed to fit)
Thin, even layer of cashew “ricotta” (~½ cup)
Layer of raw marinara (~½ cup), smoothed
Small spoonfuls of pesto, spread lightly (optional)
Repeat layers until the dish is filled, finishing with a generous top layer of marinara and a few swirls of pesto.
Compress and chill — Press layers gently with an offset spatula for a compact finish. Cover and refrigerate at least 1 hour (2–3 hours recommended) to let layers set and flavors meld.
Slice & serve — Use a sharp knife rinsed in hot water (wipe between cuts) for clean slices. Garnish each portion with fresh basil, pine nuts/toasted seeds, cherry tomato halves, and cracked pepper. Serve chilled or slightly above fridge temperature.