Soak the cashews in water for at least 2, up to 8 hours. If soaking over night, be sure to refrigerate. Drain and rinse the cashews.
Add the cashews to the food processor with garlic, nutritional yeast, and chicken stock. Blend until smooth and creamy.
Pull the rosemary leaves from the stems. Add to the cashew cream sauce and pulse until blended through. Store refrigerated for 7-10 days.