Use the coarse side of a box grater or food processor to grate potoatoes and onions separately.
Firmly squeeze liquid from grated potatoes into a large mixing bowl. Allow drained liquid to sit in the bowl for a few minutes then drain, reserving the starch that has settled on the bottom of the bowl. In a separate bowl, squeeze liquid from grated onion.
Add drained potato, onion, egg, salt and pepper to bowl with starch. Toss everything until thoroughly mixed. Set aside.
Preheat 2-3 tbsp avocado oil in a 12” non-stick skillet over medium-high heat. Form small mounds of the potato mixture in your hands, squeezing out any additional liquid that has released. Add potato mixture to hot oil. Fry latkes 4-5 minutes per side or until golden brown and cooked to your desired doneness. **If required, add more avocado oil to the pan.
Transfer cooked latkes to a tray lined with a cooling rack and season immediately with flakey sea salt. If making in advance, reheat cooked latkes in a 350F oven until warmed through (approx. 8-10 minutes).
To serve, spoon a dollop of coconut sour cream, fan slices of smoked salmon overtop and garnish with chopped chives.