Wash the cherries and remove the stems. Tip into a bowl and toss with half of the sugar, then leave them to macerate for 30 minutes.
Preheat the oven to 180°C/160°C fan/350°F. Rub the butter around the edges of a high-sided baking dish, or cake or tart tin, then sprinkle with a little flour and shake off the excess.
Sift the flour into a bowl, then add the salt and the rest of the sugar. Beat the eggs and add them to the dry mix, and beat well to combine. Pour in the milk and mix again.
Tip the cherries into the dish, then cover with batter.
Put the dish in the oven and bake for 35-40 minutes. When golden and puffed up, sprinkle with a little sugar and leave to cool. Serve cold, cut into slices.