Add the blueberries, sugar and cornstarch to a medium pot.

Cook over medium heat for 20-25 minutes until thick and the jam measures out to about ¾ cup.

Remove from the heat, transfer to a bowl and let the jam cool. Set aside 2 tablespoon of jam for the frosting.

To start, bloom your yeast. Mix your active dry yeast, sugar, and warm milk together and let sit for 10 minutes until foamy on top.

In a large bowl of a stand mixer with a whisk attachment, mix flour, salt and sugar together.

To the dry ingredients add the whisked eggs, vanilla, lemon zest and softened butter and mix.

Add in the yeast mixture and mix until everything is blended. Switch to a dough hook and knead on medium speed for 7-10 minutes until the dough pulls away from the edges of the bowl.

Form the dough into a ball, place in a greased bowl, cover and let rise for 1-1.5 hours.

While the dough rises, mix the butter, brown sugar, white sugar, lemon zest, lemon juice and salt together in a small bowl.

Grease a 9×13 inch casserole dish and set aside.

Once the dough has risen, punch it down, roll it out, and spread the lemon filling evenly over it.

Spoon the blueberry jam over the lemon filling and spread evenly.

Roll up the dough tightly into a log and cut into 12 rolls.

Place rolls in the greased dish and pour heavy cream in between each roll. Allow to proof for about an hour.

Preheat the oven to 350°F (175°C) about 15 minutes before the rolls are done proofing.

Once proofed, bake for 22-25 minutes, or until lightly golden.

Make the cream cheese frosting by mixing the softened butter until pale and fluffy.

Add in the cream cheese and mix until combined.

Sift powdered sugar into the mixture and mix until incorporated.

Add lemon zest and blueberry jam, mix until fluffy.

Let the rolls cool for 5 minutes, then spread the frosting over them.