Saute the scallion greens in a little olive or coconut oil until soft, about 2 minutes.
Add scallions to a high-performance blender with the soaked macadamia nuts, 1 1/2 cups of water, a pinch of nutmeg, and 1/2 teaspoon salt.
Blend on high until smooth and creamy. Slowly add the remaining 1/2 cup water to thin to desired consistency. Taste, adjust seasoning if needed, and use as desired.