Add the blueberries, sugar, lemon juice, vanilla extract, and cornstarch slurry to a saucepan and cook until the mixture thickens. Let it cool completely.

Add the cream cheese, and mascarpone to a mixing bowl, then mix until smooth.

Add the whipping cream and beat until light and fluffy.

Add sugar, then mix until smooth.

Add the blueberry jam and mix until well combined.

Add the softened butter and sugar to a mixing bowl.

Add the eggs and vanilla extract, then mix until well combined.

Add the lemon zest and mix well.

Add the milk and yogurt, then mix until smooth.

In a separate bowl, mix the flour and baking powder.

Gradually add the dry ingredients to the wet mixture and mix gently.

Mix until a smooth cupcake batter forms.

Divide the batter evenly among the lined cupcake cups.

Bake at 180°C (350°F) for 18–22 minutes, or until a toothpick inserted into the center comes out clean.

Let the cupcakes cool completely.

Pipe the blueberry frosting over the cooled cupcakes.

Top with blueberry jam.

Serve and enjoy.