In a big bowl, combine the flour, sugar, salt and baking powder.
Make a hole in the middle of flour mixture. Add the eggs. Lightly beat the eggs and slowly pour the milk. Whisk until smooth.
Melt the butter in a small saucepan. Add into a batter. Add the vanilla extract. Combine until smooth.
Leave the bowl of batter at the room temp. about 30 min.
Preheat oven to 225 C temp. Line a deep oven tray (40×33 cm) with parchment paper. Pour the batter into the tray.
Bake about 30 min. Cut into 12 or 16 pieces.