Preheat your oven to 375°F.
Grease the loaf pan with butter.
Mix flour, baking powder, salt, and sugar.
Add shredded cheddar cheese to dry ingredients.
Fold in diced jalapeños carefully.
Pour beer into the mixture slowly.
Stir until just combined, don't overmix.
Pour batter into prepared loaf pan.
Brush top with melted butter evenly.
Bake for 45 minutes until golden.
Cool for 10 minutes before slicing.