Place the flour, salt and eggs in a large bowl, add half the milk and whisk well until the mixture is lump free. Add the remaining milk and whisk again until smooth.
Melt the butter in a non-stick frying pan, add the leeks and sauté over a medium heat for 2-3 minutes or until soft. Add the tomatoes and cook for a further 4 minutes until just softening. Season.
Wipe out the frying pan, return to the heat and when hot, melt a little butter.
Add 3-4 heaped tablespoons of the mixture around the saucepan so they form small round pancakes.
Cook for 2-3 minutes or until the base is set. Flip over and cook for a further 1-2 minutes or until golden. Keep warm whilst you repeat with the remaining batter and butter.
Serve hot topped with the tomato and leek.