Preheat the oven to 180˚C. Lightly butter a baking sheet.
In a saucepan heat the butter, water (and milk, if using), sugar and salt until the butter has melted. Remove the batter from the heat and add the flour.
Mix with a wooden spoon to make a smooth paste. Place the dough back on the heat to dry, stirring vigorously until the dough comes away from the sides of the pan. Transfer the dough to a bowl and leave to cool for five minutes.
Beat in the eggs gradually.
Pipe 4 - 5 cm diameter rounds onto the baking sheet, sprinkle over the pearl sugar nibs. Bake in the oven for 15 minutes without opening the oven door. Lower the oven temperature to 165°C and, leaving the oven door slightly open, continue cooking for 15 more minutes or until the choux pastry is lightly golden.
Check that the choux are cooked by tapping them: if they sound hollow, they are cooked. Transfer to a wire rack to cool.
Heat the lemon juice, peel, agar-agar and sugar together. Combine with the fromage blanc (or cream cheese). Fold in the whipped cream and transfer to a piping bag with a plain pastry tip (nozzle).
Red berry coulis
Combine the red berries and sugar. Blend to a purée and strain through a fine-mesh sieve.
Slice the top off each of the choux to obtain a hat. Fill each choux with lemon cream and arrange the strawberry halves and raspberries on top. Position the hat on top.
Place a filled choux pastry on a plate and decorate with finely grated lemon peel. Draw a line of red berry coulis on the plate and serve the remainder in a sauce boat.