Creating Lemon Berry Cake is straightforward when you follow these clear steps:

1. Preheat Oven: Preheat your oven to 350°F (175°C). Grease and flour two 9-inch round cake pans.
2. Mix Dry Ingredients: In a large bowl, whisk together the flour, baking powder, baking soda, and salt.
3. Cream Butter and Sugar: In another bowl, beat the softened butter and granulated sugar until light and fluffy.
4. Add Eggs: Add the eggs one at a time, mixing well after each addition.
5. Incorporate Yogurt and Zest: Mix in the Greek yogurt (or sour cream), lemon zest, and lemon juice until well combined.
6. Combine Mixtures: Gradually add the dry ingredients to the wet mixture, stirring until just combined.
7. Fold in Berries: Carefully fold in the mixed berries, ensuring they are evenly distributed throughout the batter.
8. Divide Batter: Pour the batter evenly into the prepared cake pans.
9. Bake: Place in the preheated oven and bake for 30-40 minutes, or until a toothpick inserted in the center comes out clean.
10. Cool: Remove from the oven and let the cakes cool in their pans for about 15 minutes. Then, gently transfer them to wire racks to cool completely.
11. Frost (Optional): Once the cakes are cool, you can frost them with your favorite icing or whipped cream if desired.

These steps will guide you in creating this incredible Lemon Berry Cake effortlessly.