Lemon and thyme cake bars recipe

(9 ratings)

These lemon and thyme cake bars squares are rich, zingy and bursting with citrus flavour.

lemon and thyme cake bars
(Image credit: Future)
  • healthy
Preparation Time30 mins plus chilling
Cooking Time45 mins plus cooling
Total Time1 hours 15 mins plus chilling and cooling
Cost RangeMid
Nutrition Per PortionRDA
Calories406 Kcal20%
Fat17 g24%
Saturated Fat10 g50%
Carbohydrates57 g22%

Our lemon and thyme cake bars have a buttery base and a rich gooey lemon curd topping. 

If you like a Mary Berry lemon drizzle cake, you’ll enjoy the flavours of this sophisticated bake. It’s got luxurious, rich lemon curd and a crunchy base which is delicately scented with lemon thyme. The lemon and thyme cake bars or squares can be served as dessert or enjoyed as an afternoon treat. They are also the perfect size to take on picnics or pack into lunchboxes. 


  • 250g butter, softened
  • 125g caster sugar
  • 2tsp vanilla paste
  • 2tbsp fresh lemon thyme
  • 250g plain flour
  • 2tbsp cornflour

For the lemon filling:

  • 6 large eggs
  • 400g caster sugar
  • zest of 4 lemons, plus 240ml freshly squeezed lemon juice
  • 150g plain flour
  • Icing sugar, for dusting




  1. Line a 23x33cm baking tin with parchment. For the shortbread, cream the butter until pale, then add the sugar, vanilla and lemon thyme, and mix to combine. Sift the plain flour, cornflour and 1⁄4tsp salt together, and mix this into the butter until just combined. Turn out the dough, shape into a ball and then press flat into the baking tin. Chill for 20 minutes while you heat the oven to 180C/Gas 4.
  2. Bake the shortbread for 15 minutes before removing and leaving to cool.
  3. For the filling, whisk the eggs and sugar together until smooth, then add the lemon zest and juice, and stir. Sift in the flour and mix. Pour the filling over the shortbread, return the tin to the oven and bake for a further 30 minutes, or until just set.
  4. Leave to cool completely before dusting with icing sugar and slicing.

Top tips for making lemon and thyme cake bars

The thyme adds a delicate flavour which compliments the lemon beautifully but it will also be delicious if you leave it out. We like to finish the bars with a dusting of icing sugar and a little sprig of thyme for decoration. For tips on how to tell when the curd is set, read our tips below. 

What are the best uses for lemon thyme?

Lemon thyme is excellent in sweet and savoury recipes. It has a light, delicate flavour that balances rich fatty dishes and ingredients. In this recipe it helps contrast the luscious lemon curd-style filling but it would also work well with buttery potatoes in a light salad or a piece of hot smoked salmon. You can also make a simple but delicious hot drink from it by adding a few sprigs to your cup when you are making a green tea. Allow it to infuse with the tea bag for a few mins then discard both and enjoy. 

How do you know when lemon bars are done?

Similar to when you make a lemon tart, these lemon and thyme cake bars are ready when there is a slight wobble on the curd but not too much. It will continue to cook in the residual heat of the tin when you remove it from the oven. This is why you don’t want to wait for the curd to be completely set before taking it out otherwise it will be overcooked. 


Do lemon bars need to be kept in the fridge?

They can stay at room temperature for around an hour but any longer than that and it’s best to keep in the fridge. If the bars get too warm the curd-like filling will begin to melt and seep out. 

When you need to squeeze lemons to extract the juice you can simply use your hand but food writer Jessica Ransom sweats by this cheap and effective kitchen gadget.

ProCook Lemon Reamer - View at ProCook

ProCook Lemon Reamer - View at ProCook

You can buy these little wooden reamers from a number of shops for just a couple of pounds. It sounds silly but food writer Jessica Ransom says: ‘Using a lemon reamer is an absolute game changer when juicing lemons, limes or oranges. You extract so much more juice than if you simply squeezed with your hand. It’s one of my favourite pieces of kitchen kit and it’s cheap and takes up hardly any space in my drawers.’

If you like a gooey dessert you should try our lemon pudding. It's wonderful with cream or custard and very easy to make. You might also like our lemon meringue slice which looks impressive as a dessert or our lemon creams which can be prepared ahead. 

Keiron George
Freelance Food writer

With over 12 years of experience, arts graduate Keiron turned to food to channel his creativity, specifically cake decorating. Keiron set up his wedding cake business in 2015. And, in late 2016 won a scholarship at the world-renowned culinary institute - Le Cordon Bleu, London, where he studied the art of French Pâtisserie. He's worked in some of London’s finest 5-star hotels, collecting a wealth of knowledge along the way. As a Food Writer and Stylist food isn’t just a job, it truly is Keiron's passion.