Follow these steps to create your Lemon Raspberry Cake:

1. Preheat the Oven: Start by preheating your oven to 350°F (175°C). Prepare two 9-inch round cake pans by greasing and flouring them.
2. Mix Dry Ingredients: In a medium bowl, whisk together flour, baking powder, and salt.
3. Cream Butter and Sugar: In a large mixing bowl, beat softened butter and granulated sugar together until light and fluffy.
4. Add Eggs: Incorporate eggs one at a time, mixing well after each addition.
5. Add Lemon Juice and Zest: Stir in the lemon juice and zest until well combined.
6. Combine Mixtures: Gradually add the dry ingredients to the wet mix, alternating with the milk. Begin and end with the dry mix. Mix until just combined.
7. Pour Batter: Divide the batter evenly between the two prepared pans and smooth the tops with a spatula.
8. Bake: Place the pans in the oven and bake for 25-30 minutes. A toothpick inserted into the center should come out clean.
9. Cool Cakes: Once baked, remove the cakes from the oven and let them cool in the pans for 15-20 minutes before transferring to wire racks to cool completely.
10. Prepare Raspberry Filling: In a medium saucepan over medium heat, combine raspberries, sugar, lemon juice, and cornstarch. Cook until slightly thickened, then remove from heat and let cool.
11. Make Frosting: In a separate bowl, beat together softened butter and powdered sugar. Add lemon juice, vanilla extract, and a pinch of salt. Mix until smooth and creamy.
12. Assemble Cake: Place one cake layer on a serving platter. Spread raspberry filling evenly over the top, then add the second cake layer on top.
13. Frost the Cake: Use the lemon frosting to cover the entire cake, smoothing it out with a spatula.
14. Decorate: Optionally, garnish with fresh raspberries and lemon zest on top for an elegant touch.

These steps will help you craft a Lemon Raspberry Cake that is sure to impress!