Preheat your oven to 350°F (175°C).
Grease a 9x5-inch loaf pan with butter or cooking spray.
In a large mixing bowl, whisk together the dry ingredients: flour, sugar, baking powder, baking soda, and salt.
In a separate bowl, mix the wet ingredients: buttermilk, melted butter, eggs, and vanilla extract until smooth.
Pour the wet ingredients into the dry ingredients and stir until just combined.
Gently fold in the chopped pecans.
Pour the batter into the prepared loaf pan and smooth the top.
Bake for 50-60 minutes, or until a toothpick inserted into the center comes out clean.
Let the bread cool in the pan for 10 minutes, then transfer to a wire rack to cool completely.