Preheat & Prepare: Preheat the oven to 350°F (175°C). Grease a 9x5-inch loaf pan and line with parchment paper.
Mix Dry Ingredients: In a medium bowl, whisk together flour, baking powder, baking soda, and salt.
Combine Wet Ingredients: In a separate large bowl, whisk eggs and sugar until pale and creamy. Stir in sour cream, vegetable oil, melted butter, lemon zest, lemon juice, vanilla extract, and lemon extract.
Make the Batter: Gradually add the dry ingredients to the wet ingredients, stirring until just combined. Avoid overmixing.
Bake: Pour the batter into the prepared loaf pan and smooth the top. Bake for 45-50 minutes, or until a toothpick inserted in the center comes out clean.
Cool the Loaf: Let the loaf cool in the pan for 10 minutes before transferring to a wire rack to cool completely.
Prepare the Glaze: In a small bowl, whisk together powdered sugar and lemon juice until smooth. Adjust consistency as needed.
Glaze & Serve: Drizzle the glaze over the cooled loaf and garnish with lemon zest if desired. Slice and enjoy!