Grease a 2 pound loaf tin and heat the oven to gas mark 5,375F,190C. Place the flour, corn meal, sugar and baking powder into a bowl, and beat in the eggs, milk, oil and yoghurt. Mix all the liquids together first if you like, then pour them in. Give the mixture a good stir. At this point you could add 8 ounces of grated Cheddar Cheese or similar. Pour into the tin and bake for 55 minutes. Test with a skewer if it comes out clean it's ready, if it's a bit smeary it needs another 5 to 10 minutes, but cover the top with foil to stop the crust burning. Remove when ready and let it stand for five minutes before turning out. You may find a knife round the edge helps