Preheat oven to 375°F. Lightly coat a 9x5-inch loaf pan with nonstick cooking spray.
In a large bowl use a silicone spatula to mix together flour, beer, ½ of melted butter, and sugar just until combined and fully moistened. Be careful not to overmix.
Transfer batter to prepared loaf pan. Drizzle the reserved melted butter on top.
Bake for about 40-45 minutes or until top is golden and a toothpick inserted in the center of the loaf comes out clean. You can broil the top at the end of baking to brown further, if desired.
Cool in pan on a wire rack, for 15 minutes. Remove from pan to a cooling rack.
Cool to room temperature (slightly warm is OK) then slice and serve.
Notes
To make your own Self-Rising Flour: In a medium bowl use a whisk to combine 3 cups all-purpose flour, 1 tablespoon baking powder, and 1 teaspoon salt. Proceed with the recipe as written.