In a bowl, combine all the wet ingredients – eggs, honey, yoghurt, oil, and the flavourings (in this case, the grated lemon zest). Mix until you have a smooth, even batter.
Add the dry ingredients – flour and baking powder – and mix well. The batter will be quite thick; add the lemon juice and fold it in until combined.
Gently fold the blueberries into the batter, then transfer the mixture to a lined baking dish. Decorate with a few extra blueberries, if you like.
Bake at 180°C for about 40 minutes. Before removing from the oven, check with a skewer – if it comes out clean, the cake is ready.