Pre-heat the oven to 200°C (400℉).
In a bowl, mix together the dry ingredients (first six ingredients).
In a separate bowl, whisk together the egg and other wet ingredients, along with the jalapeños.
Stir into the dry ingredients.
Melt the 15g butter in a skillet - mine is 24cm (9½ inches).
Swirl the butter in the pan so that it also covers the sides.
Pour the batter into the skillet, smoothing over to make the top fairly flat.
Sprinkle some cheese over the top (if you like).
Bake for around 20 minutes, until golden. An inserted skewer will come out clean when ready. Serve warm. Enjoy!