Spiralize the zucchini: Use a spiralizer or a julienne peeler to make zoodles. Place them on a clean towel and sprinkle lightly with salt.
Let them sit 10 minutes to draw out moisture, then gently pat dry.
Make the pesto: In a food processor, combine basil, spinach, Parmesan (or nutritional yeast), nuts, garlic, lemon juice, and a pinch of salt and pepper. Pulse to chop.
Add oil and water: With the machine running, stream in 2 tablespoons olive oil. Add 2–4 tablespoons water until the pesto is creamy but still thick.
Taste and adjust salt, pepper, and lemon.
Quick-sauté the zoodles: Heat 1 tablespoon olive oil in a large skillet over medium heat. Add the zoodles and toss for 1–2 minutes, just until slightly tender but still crisp. Do not overcook.
Season with pepper and a pinch of red pepper flakes if you like.
Add greens and tomatoes: Toss in the spinach or arugula and cherry tomatoes for 30–60 seconds, just to warm and wilt slightly.
Fold in pesto: Remove the skillet from heat. Stir in enough pesto to coat the zoodles lightly—start with half and add more to taste. If it seems thick, splash in a tablespoon of water or a squeeze of lemon.
Plate and finish: Divide into bowls.
Top with toasted nuts, extra Parmesan, basil, or your protein of choice. Serve immediately.