First, prepare the syrup. Combine the water, sugar and lemon juice in a small pan and bring to a boil. Lower the heat and gently simmer for about 5-8 minutes.Then turn off the heat, stir in the vanilla essence and allow to cool down.
In a large bowl, mix together the semolina, flour, baking powder, sugar, coconut and salt. In a small bowl, mix the liquid ingredients, yoghurt, melted butter, eggs and vanilla. Make a well in the centre of the dry ingredients and then gradually add the liquid ingredients while mixing with a spatula or wooden spoon to form a thick batter.
Pour and level out the batter in a greased pan and lightly score the top with diamond or square shaped cuts. Press a whole almond in the middle of each square or diamond. Then cover and set the pan aside for half an hour. This helps the semolina to absorb the liquids. In the meantime, preheat the oven at 180°.
Uncover the pan and bake in the preheated oven for 40 minutes. Then remove from the oven and carefully cut all the way through the marks you had made earlier. Pour the cooled syrup as evenly as possible all over the hot basbousa. Then place the pan back in the oven and bake for an additional 5 minutes. Remove and let it rest for at least 30 minutes before cutting out the pieces and serving.