How to salt potatoes? I would use boiled or fried potatoes inside other recipes like the Spanish tortilla which has usually a salty taste. Depending on how I cut the potatoes however, sometimes there is too much contrast between how salty mix and the potato chunks.

I wonder if there is a way I could salt the potatoes correctly before adding them to de mixture.

For instance, for the tortilla I mention, the spuds are cooked in olive oil for about 30min. Adding salt to the oil while cooking had little effect. I was thinking about leaving them in salty water for a while, but that would take a long time and pre-boiling it, doesn't seem to fit the recipe.. so..?
Add the salt in te bowl of egg and potato mixture, right before pouring the mix to the pan. You don't salt the potatoes you salt the whole tortilla. 

Even if you use onion. The onion inside the Spanish tortilla tastes always sweet.