Making Blueberry Sour Cream Coffee Cake is a fun and rewarding process! Just follow these easy steps:

1. Preheat Oven: Begin by preheating your oven to 350°F (175°C). Grease a 9-inch round cake pan or line it with parchment paper for easy removal.
2. Combine Dry Ingredients: In a medium bowl, whisk together the flour, baking powder, baking soda, and salt. Set aside.
3. Cream Butter and Sugar: In a large mixing bowl, beat together the softened butter and granulated sugar until light and fluffy.
4. Add Eggs and Vanilla: Mix in the eggs one at a time, followed by the vanilla extract. Beat until well combined.
5. Incorporate Sour Cream: Gradually add the sour cream to the mixture, stirring gently until smooth.
6. Combine Mixtures: Slowly fold in the dry ingredients until just combined. Avoid over-mixing to keep the cake tender.
7. Add Blueberries: Gently fold in the blueberries and lemon zest, if using, until evenly distributed.
8. Pour into Pan: Transfer the batter to the prepared cake pan, smoothing the top with a spatula.
9. Sprinkle Cinnamon Sugar: For that extra touch of flavor, sprinkle cinnamon sugar on the top of the batter.
10. Bake: Place in the oven and bake for 35-40 minutes, or until a toothpick inserted in the center comes out clean.
11. Cool: Remove the cake from the oven and let it cool in the pan for about 10-15 minutes. Then, transfer it to a wire rack to cool completely.

By following these steps, you’ll create a cake that is both delicious and visually stunning!