Preheat the oven to 180C/160C Fan/Gas 4. Grease the tin with baking spread and line the base with baking paper.
Measure all the ingredients into a large bowl and beat for 2 minutes, or until well blended. Turn the mixture into the prepared tin and level the top.
Bake for 35–40 minutes until the cake has shrunk a little from the sides of the tin and springs back when lightly touched with a fingertip in the centre of the cake.
Meanwhile, make the glaze. Mix the granulated sugar with the lemon juice and stir to a runny consistency.
Leave the cake to cool for 5 minutes in the tin, then lift out, with the lining paper still attached, and place on wire rack set over a tray.
Brush the glaze all over the surface of the warm cake and leave to set. Remove the lining paper and cut into slices to serve.
Tip 1: It is important to spoon the glaze on to the cake while it’s still warm so the lemon juice soaks in properly.
Tip 2: Lemon balm works well as an alternative for lemon verbena if you can’t get hold of any, or you could use finely chopped lemon thyme leaves.
Tip 3: This traybake can be stored in an airtight container for 3–4 days and frozen for up to a month.