Preheat oven to 180 degree C.
Cream together butter, sugar, till light and frothy.
Add the dissolved flax seed powder.
Blend in yogurt and buttermilk.
Sift all dry ingredients and add them to the prepared mix.
Stir in the lemon zest and walnuts.
Pour the batter in a lined and greased baking tin.
Bake for 30-40 minutes or until a tooth pick comes out clean.
Make the glaze by simmering in all ingredients under Lemon Glaze.
When the cake is done, pour the lemon glaze over the hot cake and return to the oven for 10 minutes.
Let the cake cool a little before cutting it.