Separate the 3 Medium Eggs, being careful not to get any yolks in the whites. Clean your mixing bowl and beaters really well, then rub half a lemon in the bowl and on the beaters. This helps the egg whites beat better.
Beat the egg whites till they increase in volume, stiff or firm peaks are formed.
Next break up the 140 grams Plain Chocolate into pieces, before melting in the microwave, in 30 second bursts. Do not heat any longer than 30 seconds or you run the risk of burning and ruining your chocolate. Mix in-between each 30 second burst. Alternatively, you can melt the chocolate in a bowl on top of a pan with barely simmering water.
Leave to the side for a minute or two, then gradually add in your 100 ml Milk, 1 tsp Coffee Granules and then the 2 tbsp Cocoa Powder in a large bowl! Whisking together until relatively smooth (don’t worry if a bit lumpy).
Pre-heat your oven to: 170°c/150°c Fan Oven/325°c/Gas Mark 3.
Add the softened 156 grams Butter & 140 grams Light Brown Sugar to a different mixing bowl & beat till creamed together & spreadable. (You can use the same beaters from whisking the egg whites).
Then beat in the egg yolks, 4 tbsp Greek Yoghurt and melted chocolate mixture, mixing well in-between each addition & beat for 1 minute.
Sieve over the 200 grams Plain Flour and 1 tsp Bicarbonate Of Soda (Baking Soda), and fold in gently by hand. Fold like the spatula is your pen and the batter your paper, as if you were writing a number '8'. TOP TIP - A rubber or silicone spatula is advised, rather than something metal.
Finally, fold the whisked egg whites into the prepared cake batter. Do in increments of 3. Folding in a ⅓ of the whites to begin with, will be a little easier, and loosen the batter a little, making the next 2 additions easier to incorporate. This stops knocking out the air that is in the whisked egg whites. Fold only until no more white is visible and be sure to check the bottom of the bowl.