The day before, caramelise 100 g sugar with 4 tablespoons of water in a pan until golden brown. Pour into an ovenproof pudding mould (approx. 800 ml content; alternatively a small box mould) and let it cool down.
Preheat oven (electric cooker: 150 °C/circulating air: 125 °C/gas: see manufacturer). Dissolve espresso powder in 5 tbsp. hot water. Whisk espresso with cream, milk, 75 g sugar, eggs and egg yolk. Pour through a sieve onto the caramel in the mould.
Place the mould on the fat pan (deep baking tray) and pour on so much hot water that the mould for 2⁄3 is in the water. Leave in the hot oven on the lower shelf for about 1 hour. Remove from the oven, let it cool down and put it in a cool place overnight.
The next day mix lemon juice and 1 teaspoon sugar. Wash, halve and stone the peaches and cut them into thin slices. Remove seeds from melon. Cut the flesh from the skin and dice finely.
Mix fruit with lemon juice. Turn over flan and serve with fruit salad.