Preheat oven to 300 degrees. Lightly coat the insides of a 9-inch spring form pan.
In a double boiler melt chocolate along with the butter and Nescafe.
Transfer to a bowl and cover with saran wrap.
In a double boiler place the eggs and yolks in pan. Whisk until eggs are 110 degrees about 2 to 3 minutes.
Transfer the eggs to the bowl of an electric mixer. Whisk on high until eggs become light in color.
Remove bowl and fold in a third of the eggs into melted chocolate. Add the remaining eggs and fold gently.
Pour into pan and bake 1 hour to 1 hour 15 minutes until the internal temperature of the cake reaches 170 degrees.
Cool for 45 minutes pressing down the sides to make the cake as flat a surface as possible. Remove sides but leave bottom.