Leave the skin on your cucumber. Slice your cucumber in half lengthwise. Remove seeds and then slice thin.
Mix everyhting in a large bowl, cover and place in your fridge while you make everything else.
In a medium bowl, rough mash your avocados. Add in the rest of the ingredients and mix to combine.
Pat your fish dry with paper towel. Slice the filet into large chunks. Transfer to a bowl and mix with the seasonings, lime zest and juice to coat.
In a large skillet, working in two batches, add 1/2 tbs olive oil. Once pan is hot add in the salmon pieces and cook until crispy and done. Remove to a plate lined with paper towel. Wipe the pan clean and repeat with the rest of the salmon.
Heat your tortillas in a pan or wrapped in a stack, in aluminum foil in your small toaster oven.