Pre-heat the oven to 160°C/325°F/Gas 3.
Place all the ingredients into a large bowl and beat well for approximately 2 minutes or until well blended.
Turn the mixture into a traybake tin, 30 x 23 x 4 cm (12 x 9 x 1 ½ inches) lined with non-stick baking parchment levelling the mixture carefully with a spatula.
Bake in the middle of the oven for 25 to 30 minutes or until it springs back when you press the middle of the traybake with your finger.
Once removed from the oven allow to cool for a few minutes before lifting the traybake from the tin by the lining paper. Remove the lining paper carefully and place on a wire rack with a tray underneath to catch the drizzle topping.
Mix the lemon juice and granulated sugar in a bowl and spoon this mixture evenly over the traybake while it is still warm and cut into squares.
For a change add 40g of poppy seeds or spread 150g of blueberries over the mixture before you put the traybake into the oven.
Iain Watters has provided this recipe to support Wallace & Gromit's BIG Bake
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