Add all pesto ingredients to a blender and process until a smooth paste. Set aside.
Cook soba noodles according to the instructions on the package. When al dente, drain and set aside.
Heat cooking oil over medium heat. Sauté onion until fragrant. Add garlic and cook for 1-2 minutes more. Then add cherry tomatoes and cook until they start to soften.
Add spiralized zucchini and spinach. Cook until the zucchini noodles are soft and spinach has wilted.
Then add soba noodles. Cook until heated through before stirring in the pesto.
Optional: serve with roasted sunflower seeds and fresh chives on top.