Preheat your oven to 325F / 170C. Grease a loaf tin and line with parchment.
Whisk together the flour, baking powder and salt in one bowl and set aside.
Add the butter and granulated sugar to another bowl. Cream together until pale yellow and well combined.
Beat the eggs, and slowly add to the butter and sugar. Add in two or three increments, fully combining before adding more.
Stir in the vanilla and lemon zest.
Add half of the flour and milk and fold in, before adding the remaining flour and milk, combining so no dry flour is left.
Fold in the raspberries.
Pour the cake batter into the prepared loaf tin.
Bake for around 1 hour, until golden brown and an inserted toothpick comes out clean.
Take the cake out of the oven and rest for 10 minutes before removing it from the tin and placing it on a cooling rack. Let cool completely before glazing it.
Whisk together the lemon zest and confectioners' sugar and drizzle over the cake.
Notes
Use room temperature ingredients to make the pound cake batter. This will allow the ingredients to combine more easily so that you have an even texture throughout the cake.
Beat the eggs and the sugar really well together until it is a light yellow in color.
The quickest way to make the cake batter is using an electric hand mixer. You can make it by hand, but it will take a little while longer, and make sure that everything is well mixed.
Test that the cake is done by inserting a toothpick into the center. It should be clean when you remove it.
Let the lemon raspberry pound cake cool completed before icing it. It's best to place the cake on a cooling rack to let the air circulate.