Preheat your oven to 350°F (175°C) and grease or line a 9x5-inch loaf pan.
In a large mixing bowl, whisk together the flour, sugar, baking soda, salt, and cinnamon until combined.
In another bowl, beat the softened butter, buttermilk, eggs, and vanilla extract until smooth.
Slowly pour the wet ingredients into the dry ingredients, mixing gently with a rubber spatula until just combined. Do not overmix.
Fold in the chopped pecans.
Pour the batter into the prepared loaf pan, smoothing the top with the spatula.
Bake in the preheated oven for 50 minutes or until a toothpick inserted into the center comes out clean.
Let the bread cool in the pan for about 10 minutes before transferring it to a wire rack to cool completely.
For extra flavor, consider adding a teaspoon of nutmeg or a pinch of allspice along with the cinnamon.
Store any leftovers in an airtight container for up to 3 days at room temperature or freeze for longer storage.