Brush an 8 x 21cm (base measurement) loaf pan with the melted butter to grease.
Preheat oven to 220&deg;C. Heat oil in a non-stick frying pan over medium-high heat. Add capsicum and cook, stirring, for 5 minutes or until capsicum is tender. Add cumin and cook, stirring, for 1 minute or until aromatic. Set aside for 5 minutes to cool slightly.
Combine the flour, cornmeal, baking powder and salt in a large bowl. Add the corn kernels, jalapenos, coriander and capsicum mixture, and stir until well combined. Add the buttermilk, melted butter and egg, and use a wooden spoon to mix until well combined.
Pour into prepared pan and smooth surface with the back of a spoon. Bake in preheated oven for 30-35 minutes or until a skewer inserted into the centre of the loaf comes out clean.
Remove from oven and stand for 5 minutes before turning onto a wire rack. Set aside for 15 minutes to cool slightly. Serve warm or at room temperature.