Begin by preheating your oven to 350°F (175°C). This ensures that the cake bakes evenly.
Grease your 9x5-inch loaf pan with butter or non-stick spray, then lightly dust it with flour.
In a medium bowl, whisk together the all-purpose flour, baking powder, and salt. Set this mixture aside.
In a large mixing bowl, use an electric mixer to beat the softened butter and granulated sugar together until light and fluffy, about 3-5 minutes.
Add the eggs one at a time, mixing well after each addition.
With the mixer on low speed, add the buttermilk, fresh orange juice, orange zest, and vanilla extract, mixing until just combined.
Gradually add the dry ingredient mixture to the wet ingredients, mixing until just combined.
Pour the batter into the prepared loaf pan and smooth the top with a spatula. Bake for 60-70 minutes, or until a toothpick comes out clean.
While the cake is baking, prepare the glaze by mixing together the granulated sugar, fresh orange juice, powdered sugar, and additional orange juice until smooth. Stir in the orange zest.
Once the cake has finished baking, let it cool in the pan for about 15 minutes before transferring it to a cooling rack. Once completely cooled, drizzle the orange glaze over the top.
