For the madeleines:

1. Preheat the oven to 400°F (200°C). Brush the madeleine tray with melted butter or cooking spray, and shake in a little flour to coat, tapping out the excess.
2. Whisk together the eggs and the sugar in a bowl until frothy. Lightly whisk in the remaining ingredients. Leave to stand for 20 minutes before carefully pouring into the prepared madeleine tray.
3. Bake for 8-10 minutes, or until the mixture has risen a little in the middle and is fully cooked through. Transfer the madeleines to a wire rack and leave for a few minutes to cool slightly.

For the madeleine syrup:

1. In a small saucepan, mix sugar and water. Bring to the boil and simmer for 2 minutes. Add the rum, and simmer one more minute. Leave to cool.

For the strawberry mousse:

1. Remove the stems from the strawberries. Heat the strawberries in a small saucepan with half of the sugar, stirring to break down the strawberries and creating a puree.
2. Push the hot strawberry puree through a fine sieve to remove the seeds. Discard the seeds and set the puree aside.
3. Cover the gelatine leaves with cold water in a clean bowl. In another bowl, whisk egg yolks with the remaining caster sugar. Pour the hot strawberry puree onto the yolk-sugar mixture and whisk continuously.
4. Transfer into a saucepan and heat whilst continually mixing until the puree thickens and coats the back of a spoon.
5. Drain and squeeze out the gelatine leaves, and add them to the hot strawberry puree. Stir and set aside to cool.
6. Using an electric hand whisk, whip the whipping cream to soft peaks, adding the seeds from the vanilla bean half way through.
7. When the strawberry puree is cool, fold in the whipped cream in two additions to create a smooth and creamy mousse.

To build the Charlotte:

1. Line a 9-inch (22 cm) springform with removable bottom with baking paper.
2. Cut the madeleines in half lengthways and line the tin with the curved sides against the wall of the tin. Damp some of the remaining madeleine halves into the syrup, one by one, and use them immediately to cover the bottom of the springform.
3. Using a ladle, carefully cover the madeleines with half the mousse.
4. Add a final layer of the madeleines damped into the syrup, and cover with the remaining mousse, leaving some space at the top (the madeleines on the sides should be higher than the mousse). If there is some mousse leftovers, pour into one or two ramekins.
5. Place the cake in the fridge to set for at least 3 hours. When set, gently remove the cake from the springform tin and place on a serving plate or cake stand. Decorate with mixed summer fruits.