Place the salmon and lemon juice in a bowl with 1 teaspoon of the dill. Cover and marinate in the fridge for at least 1 hour.
Make the choux pastry
Preheat the oven to 180 C / Gas 4. Line a baking tray with baking parchment.
Heat the milk, water, salt and butter in a large saucepan over low heat. Just before the mixture comes to the boil, remove from heat and whisk in the flour all at once. Return the pan to low heat and stir continuously until the paste begins to dry and detaches from the sides of the pan. Let cool 5 minutes, then add the eggs one by one, stirring until fully incorporated.
Using a piping bag fitted with a nozzle, pipe the pastry either into small puffs or into the shape of small fish onto the prepared baking tray.
Bake in the preheated oven until the pastry is puffed and golden brown and the bottom of the pastry is firm, 25 to 30 minutes. The pastry should be hollow in the centre. If it is undercooked, it will deflate when cooled. Remove to cool on a wire rack to keep the bottom of the pastry crisp.
Make the salmon mousse
Blend the smoked salmon with the cream cheese in a food processor. Add the ricotta cheese, the remaining teaspoon of dill and the marinated salmon and blend well. Refrigerate until ready to assemble.
Assemble the pastries
Assemble the pastries no more than 1 hour before serving. Cut the pastry in half horizontally with a serrated knife. Spread the mousse in the centre and replace the lid. You may use whole cloves to make "eyes" on the fish.
I serve this with orange and grapefruit sections on a little rocket or lamb's lettuce.