• Preheat the oven to 180C. Grease and line an 20 x 20cm square tin or a 25 x 17 cm rectangle tin.
• Cream the sugar, butter and lemon zest together in a large mixing bowl until fluffy and soft. Beat in the eggs one at a time - it’s okay if it looks like the mixture is curdling. Stir in the yogurt. Add in both flours, the baking powder, bicarbonate of soda and salt and fold in gently until just combined.
• Pour the batter into the prepared tin and bake for 35-40 minutes until it’s golden on top and a toothpick inserted into the centre of the cake comes out clean. Dilute the elderflower cordial with 2 tbsp of water in a small bowl and spoon this over the warm cake to soak in. Set aside to cool before frosting.

For the buttercream:

• Blitz the strawberries and lemon juice together in a blender/food processor or in a jug using a hand blender. Pour the blended mixture into a medium pot and heat over a medium-low heat, stirring occasionally, until the liquid is reduced down to about 60ml. Let it cool - this is your strawberry ‘jam’.
• Beat the softened butter together with 200g of the icing sugar. Gradually mix in the strawberry 'jam', until you have a loose but spreadable consistency. You can add more icing sugar to thicken, if needed. Spread this over the cooled cake and top with the extra strawberries (I slice them) to decorate.