Grease and line 2 small loaf pans and preheat oven to 160C (350F).
Sift flour, baking powder and salt together and set aside.
Using a stand mixer or hand beaters cream butter and sugar together until pale and fluffy.
Add eggs, one at a time, beating well after each addition.
At low speed, beat in flour alternatively with milk mixing until combined.
Stir in lemon rind and lavender.
Pour into pans and bake for 45 minutes or until a cake tester inserted into the centre comes out clean.
While cake is cooking, prepare the syrup.
Combine the lemon juice and sugar in a small pan over medium heat for 1-2 minutes, until syrupy. Allow to cool for 10 minutes.
When cakes are removed from the oven and still hot, pierce them at regular spaces with a skewer, then pour the syrup over very slowly - allowing it to soak in.
Cool in pans for 10-15 minutes, then remove and place on wire rack to cool completely.