First prepare the pudding.
Mix cold milk with pudding powder and sugar.
Mix everything and put it on the fire to cook until thickened.
If you don't have blueberry pudding, take a regular one, and then add blueberry puree, for example, 50 gr.
Well, in general, look at the color saturation.
So, we boil our pudding, remove it from the fire, cover it with a film and put it to cool.
I put it in cold water. We'll need some warm pudding.