Heat milk and butter to about 90-95° in a microwave safe bowl. Butter does not need to be completely melted.

Add yeast and sugar to milk and butter, and mix well. Set aside about 5-10 minutes, until yeast starts to bubble. 

Beat eggs in a large bowl and add in milk and yeast mixture.

Mix in 2 cups of flour along with kosher salt, stirring well.

Add flour about a 1/4 cup at a time until mixture starts to form a ball and comes away from the bowl, about 1 cup. 

Add dough onto a lightly floured surface.

Knead dough for 3-5 minutes or until dough is no longer sticky. 

Cover dough and set aside to rise at least one hour or until doubled in size.

Meanwhile, prepare the blackberry filling. Adding fresh or frozen blackberries to a saucepan with sugar, cornstarch and lemon juice. 

Cook over medium- high heat until mixture starts to boil. Lower to medium heat, stirring until thickened. Set aside to cool. 

Punch down dough and roll into a rectangle, about 12 inches x 12 inches in an even thickness.

Spread blackberry pie filling over dough and roll up, pinching the seam together to seal.

Slice into 12 slices using a serrated knife. Carefully place on a greased jelly roll pan or pie plate about 2 inches apart.

Cover and allow rolls to rise while you preheat the oven to 375°.

Bake rolls for 17-20 minutes or until golden brown and centers of rolls are baked through. 

Prepare the cream cheese frosting by adding cream cheese, powdered sugar, cream and vanilla to a mixer, beating until light and fluffy.

Allow rolls to cool at least 10 minutes or completely before icing.