Let the raspberries thaw. Chop the chocolate and melt in a hot water bath, put aside. Cut the vanilla pod lengthwise and scrape out the pulp. Peel bananas, sprinkle with lemon juice and mash finely with a fork.
Whip the sour cream, 50 g sugar and vanilla pulp with the whisks of the mixer. Loosely fold in the banana puree. Pour the cream into a flat casserole dish (approx. 20 x 30 cm) and smooth it down. Using a spoon, drizzle liquid chocolate in strips onto the cream. Let it freeze in the freezer for at least 30 minutes.
Set some raspberries aside, mash the rest and pass through a sieve. Fill up raspberry puree with water to 200 ml. Caramelise 80 g sugar in a pot until golden brown, add raspberry puree and simmer for 6-8 minutes. Spread iced banana cream, raspberry caramel and the raspberries in layers in six glasses and serve immediately. Cantuccini are delicious with it.
Tip: Don't stress yourself! Raspberry caramel and sour cream can easily be prepared the day before. Then freeze the cream overnight and put it in the fridge about 1 hour before serving. Shortly before the dream come true, just pile it up loosely.