Making your Lemon-Rosemary Layer Cake can be a delightful experience if you follow these steps:

1. Preheat the Oven: Set your oven to 350°F (175°C). Coat three 9-inch round cake pans with butter and dust with flour.

2. Mix Dry Ingredients: In a large bowl, whisk together flour, baking powder, and salt.

3. Cream Butter and Sugar: In another bowl, beat the softened butter and granulated sugar until light and fluffy.

4. Add Eggs and Flavorings: Incorporate eggs, one at a time, mixing well after each addition. Stir in the vanilla extract and lemon zest.

5. Combine Mixtures: Gradually add the flour mixture to the butter mixture, alternating with buttermilk. Mix until just combined.

6. Add Rosemary: Gently fold in the chopped fresh rosemary until evenly distributed.

7. Divide Cake Batter: Divide the batter equally among the prepared cake pans.

8. Bake: Place in the preheated oven and bake for 25-30 minutes or until a toothpick inserted in the center comes out clean.

9. Cool the Cakes: Once baked, allow the cakes to cool in their pans for 10 minutes, then turn them out onto wire racks to cool completely.

10. Prepare the Frosting: In a medium bowl, beat together softened cream cheese, powdered sugar, and lemon juice until smooth and creamy.

11. Assemble the Cake: Once the layers are completely cool, place the first layer on a cake stand. Spread an even layer of frosting on top, followed by the second layer. Repeat the process with the third layer.

12. Frost the Top and Sides: Cover the top and sides of the assembled cake with the remaining frosting.

13. Garnish: Finish with fresh rosemary sprigs and lemon slices for decoration.

14. Serve: Slice, serve, and enjoy your incredible Lemon-Rosemary Layer Cake!