In a large bowl, mix together the sourdough discard, warm milk, sugar, and melted butter. Add in the eggs and mix until well combined.

Gradually stir in the flour, salt, and instant yeast until a dough forms.

Turn the dough onto a floured surface and knead it for about 5-7 minutes until it becomes smooth and elastic.

Place the dough in an oiled bowl, cover it with a kitchen towel, and let it rise in a warm spot for 1 hour or until doubled in size.

While the dough is rising, mix the brown sugar and cinnamon in a bowl; set aside.

Once the dough has risen, roll it out into a rectangle about 1/4 inch thick. Spread the softened butter over the surface, then sprinkle the cinnamon sugar mixture evenly on top.

Starting from the long edge, carefully roll the dough into a tight log. Pinch the seams to seal.

Cut the log into equal pieces about 1-2 inches thick and place them in a greased baking dish.

Cover the rolls and let them rise for another 30 minutes.

Preheat the oven to 350°F (175°C) and bake the rolls for about 20-25 minutes or until they are golden brown.

While the rolls are baking, mix the cream cheese, butter, powdered sugar, and vanilla until smooth.

Once baked, spread the frosting over the warm rolls and enjoy!