Step 1: Preheat oven to 350°F.
Step 2: Line a baking sheet with parchment paper. Add the onion, garlic, broccoli, zucchini and celery. Drizzle with olive oil and season with salt and pepper.
Step 3: Roast the vegetables until soft, approximately 20–25 minutes.
Step 4: While the vegetables roast, boil the cashews in water until softened, then drain.
Step 5: Bring a large pot of salted water to a boil. Cook one 454 g package of Kaslo Sourdough Spaghetti according to the package instructions until al dente. Reserve a little pasta water before draining, if desired.
Step 6: Add the softened cashews, roasted vegetables, kale or spinach, vegetable stock, lemon juice and nutritional yeast to a blender. Blend until smooth, adding a little extra vegetable stock or reserved pasta water if needed to reach your desired consistency.
Step 7: Season the sauce with salt and pepper to taste. Pour over the cooked spaghetti and toss until evenly coated.
Step 8: Serve warm and enjoy your veggie-packed pasta!