Slice the napa cabbage in 1 inch slices. Add to a large mixing bowl and salt liberally. Massage into the cabbage until it starts to soften. Fill the bowl with enough water to cover the cabbage and let sit for at least 30 minutes. If needed, set a plate or other object on top of cabbage to keep submerged.
Using colander, drain and rinse out cabbage. Squeeze out most of the liquid. Set aside.
In another mixing bowl, combine ginger, chili flakes, garlic and fish sauce. Mix well until a paste forms.
Slice radishes and carrots into match stick forms and add to the cabbage. Slice ramps into 1 inch pieces and add also. Cut scallion greens into similar long strips, with the bottoms of both sliced thinly and mixed together.
Add paste to vegetables and mix well. You may opt to use gloves for this portion. When combined well, add to glass jars, pushing down to allow a bit of the liquid to rise to the top. Place lid on each jar and set in room temperature to allow to ferment for about a week. Check often, allowing gases to release. Once ready, store in refrigerator to keep fresh. Enjoy! Great served with eggs, on salads, a side for seafood or addition to soups!