Preheat your oven to 180°C (350°F). Grease the cake pan and line it with parchment paper.
In a large mixing bowl, cream together the softened butter and caster sugar until the mixture is pale, fluffy, and slightly increased in volume, about 3-4 minutes using an electric mixer or whisk.
Add eggs one at a time, beating well after each addition. The batter might look a bit curdled—this is normal. Mix in lemon zest and lemon juice gently.
Sift the flour, baking powder, and salt into the bowl. Gently fold the dry ingredients into the wet mixture until just combined. Do not overmix to keep the cake tender.
Pour the batter into the prepared cake pan, smoothing the top with a spatula. Bake for 40-45 minutes, until the cake is golden and a skewer inserted into the center comes out clean.
While the cake bakes, prepare the glaze by mixing sifted icing sugar with lemon juice until smooth. The glaze should be pourable but not runny.
Once baked, remove the cake from the oven, and let it cool in the pan for 10 minutes. Then transfer to a wire rack and cool completely before glazing.
Poke small holes in the cooled cake with a skewer, then pour the lemon glaze evenly over the top. Let it soak in and set for about 15 minutes.
Slice the cake once the glaze has set and serve at room temperature. Enjoy the moist crumb and bright citrus flavor with each bite!