Combine the yeast, honey and 125ml of lukewarm water in a bowl, then set aside for 5 minutes, or until starting to bubble. Melt the ghee in a small pan over a low heat. Meanwhile, combine the flour and ½ tablespoon of sea salt in a large bowl and make a well in the middle. Pour 1 tablespoon of the melted ghee into the well, followed by the yoghurt and yeast mixture, then beat the wet ingredients together with a fork. Gradually start incorporating the flour from the sides until it starts to form a rough dough, then bring it together with your hands – it should be soft and sticky, so add a splash more water, if you think it needs it. Knead the dough on a flour-dusted surface for around 5 minutes, or until smooth, then place into a lightly floured bowl. Cover with a clean tea towel and leave in a warm place for 1 hour 30 minutes, or until doubled in size. Once risen, knock back the dough with your fist, then divide into 6 balls. Roll each portion into an oval shape, roughly 1½cm thick. Heat a large non-stick frying pan over a high heat, add a naan bread and cook for 5 to 6 minutes, or until cooked through, turning halfway. Brush with a little of the remaining ghee, sprinkle over a few nigella seeds and a small pinch of salt. Keep warm in the oven while you make the remaining breads. Delicious served with your favourite curry.