Heat milk in a small saucepan until simmering.

In a medium sized bowl, whisk together egg yolks, cornstarch, and sugar until well-combined. Mixture will be thick at first, but will loosen up and turn a pale yellow color.

Gradually pour in the heated milk into the egg yolk mixture, swiftly whisking as you pour to quickly incorporate the milk.

When you've fully combined the two mixtures, return the entire mixture to the saucepan and cook over medium low heat, whisking constantly until it starts to thicken.

Immediately remove from heat and stir in vanilla and butter. Transfer pastry cream to a heatproof bowl, and whisk in the greek yogurt.

Cover with plastic wrap, pressing the plastic wrap directly against the surface of the cream. Refrigerate for 1 hour or until chilled.

Cut and Shape danish pastry dough according to taste. Brush the Danish pastries with the egg wash, arrange them about 3 inches apart on lightly buttered baking sheets, and let them stand for 1 hour. Bake the Danish pastries in the middle of a preheated 350°F.oven for 30 to 35 minutes, or until they are crisp and golden.

Finally, add the greek yoghut pastry cream on it. And add fruit for garnish.