1. Prepare the cake pan : Brush the base and the sides of a 15cm cake pan with a little of the melted butter. Line the sides and the bottom with parchment paper. For the side, the paper height should be a bit higher than the mold as the cheese cake will rise. Tip : If you use a loose-bottomed cake tin, then also wrap the bottom of the tin with double sheets of foil, so as to seal it completely.
2. Making the bottom of the cake Put the flour, sugar, salt, coffee powder and butter in the food processor. Pulse several times to mix until the dough comes together.
3. Spread the cookie mix or roll it out on the baking sheet appropriately and bake for 15 to 20 mins at 170C degree. Remove from the heat and press the cookie mixture into base while it is hot (otherwise it will be too hard once it cools down). Set aside.
4. In a medium size bowl, using an egg beater, mix together cream cheese and sugar (40g) until it becomes smooth.
5. Add the egg yolks one at a time and mix them each time.
6. Sift cake flour on it and mix well until incorporated. Add the melted butter and mix. Then add grated parmesan cheese (optional) and mix.
7. Add heavy cream (liquid), milk into the bowl and mix, then add yogurt, mix well them again.
8. Place the egg whites in a large clean bowl (or the stand mixer), use an electric mixer to beat them, adding rest of the sugar (40g) graduately until SOFT peaks.
9. Take about 1/3 of the egg whites and fold them into the egg yolk mixture, mix well. Add the remaining egg whites and mix gently using spatula until the batter is evenly combined.
10. Pour the mixture into the cake pan. Tap the bottom of the cake pan a few times to release any air pockets in the mixture.
11. Bake the cheese cake in a water bath in an oven preheated at 160C° for about 30 mins. Then reduce the heat to 130C° for another 25 to 30 mins. Turn off the oven and leave the door slightly opened to cool down the cake in the oven. This should prevent the cake from shrinking.
12. Remove the cake pan from the oven.
13. Microwave apricot jam and some water in a small bowl for 15 sec. Set aside until the cake is ready.
14. When the cake is out from the oven, brush the jam mixture over the top of the cheesecake. Let the cake cool to room temperature, unmold, then chill in the refrigerator before serving. You can store it in the fridge for up to 3-4 days.