Butter a baking dish, add the prunes, then pour in your batter.

Preheat the oven to 350°F (180°C). Heat the milk with the vanilla until it just begins to boil.

Crack the eggs and mix with the sugar. Add the flour, then the hot milk, and stir well. Pour into the dish and bake for 35 to 40 minutes, depending on your oven (35 minutes was enough for me).