Open the vanilla pod in half lengthwise. Carefully scrape out the seeds using the back of a knife or a teaspoon.
Mix the seeds or vanilla paste with the condensed milk.
Whip the cream until nice and fluffy.
Add approximately 1/3 of the whipped cream to the condensed milk and mix. Add that mix to the rest of the whipped cream and use a spatula to mix using folding movements.
Place the mix in a container and take it to a freezer overnight.
Place the butter, flour, salt and sugar in a bowl.
Pinch the butter with the rest of the ingredients until no pieces of butter remain and it looks like wet sand.
Add the egg and water and mix with a spatula until it doesn't help you any more. Finish mixing with your hands but don't knead or the dough will turn tough and won't roll our nicely.
Wrap the dough in cling film and place it in the fridge for 30min. If you leave it in there for longer and it turns hard then take it out of the fridge and allow it to return to room temperature before rolling it out.
Roll out the dough on a flour-dusted surface until it's 3mm thick. Don't stretch it any thinner than that or the juices from the fruits could break it. Make sure that it's not sticking to the table after every rolling motion and add more flour to the surface if necessary. Try to keep it in a round shape.
Cut the dough using a knife and using a large plate as a mould.
Place the dough on a baking tray lined with baking paper or a silpat.
Mix everything and spread it at the center of the dough. Leave about 4cm without covering around the edge so you can fold the dough onto the filling.
Fold the dough onto the filling to form the galette.
Whisk the egg with the water and use it to paint the edges.
Sprinkle a bit of granulated sugar on the edge for a nice finish.
Place in a preheated oven at 180C for 45min. If it's already golden before that then cover it with tin foil to prevent it from going darker. The galette needs to be in the oven at least 45min in the oven for the cornflour tocook through. If the dough is still pale after this time you can leave it in for longer.
Let it cool for 20min before cutting it. Serve warm with a scoop of vanilla ice cream.
If you're using frozen berries let them thaw completely on a sieve in a bowl so all the liquid gets drained. At this point you can use the berries for the galette and the juices for something else :)