- Preheat your oven to 350°F (175°C). Grease a 9x5-inch loaf pan or line it with parchment paper. 
- In a large mixing bowl, combine the flour, sugar, baking powder, baking soda, and salt. Whisk together until well mixed. 
- In another bowl, cream the softened butter until light and fluffy. Add the eggs one at a time, mixing well after each addition. Stir in the vanilla extract and sour cream until fully combined. 
- Gradually add the wet ingredients to the dry ingredients, mixing until just combined. Be careful not to overmix. 
- Gently fold in the cherries and walnuts (if using) until evenly distributed throughout the batter. 
- Pour the batter into the prepared loaf pan and smooth the top with a spatula. 
- Bake in the preheated oven for 55-65 minutes, or until a toothpick inserted into the center comes out clean. 
- Allow the bread to cool in the pan for about 10 minutes before transferring it to a wire rack to cool completely.