Preheat the oven to 200°C and line a Swiss roll tin with parchment.
Wilt the spinach and squeeze out all moisture until dry.
Pulse spinach, 4 egg yolks, baking powder, salt, and pepper in a processor until finely chopped.
Whisk 5 egg whites until stiff and fold them into the spinach mixture.
Spread the mixture into the tin and bake for 8-10 minutes until firm.
Turn the roulade onto baking parchment sprinkled with Parmesan and allow to cool.
Mix cream cheese, crème fraîche, lemon zest, dill, salt, pepper, and lemon juice until smooth.
Remove top parchment and spread filling over the sponge followed by a layer of salmon.
Roll the roulade tightly from the short end, trim the edges, and serve.