In a saucepan, combine the cubed peaches, granulated sugar, and lemon juice. Cook over medium heat for about 12–15 minutes, mashing occasionally until the mixture thickens.

Stir together cornstarch and water in a small bowl; mix this into the peach jam and cook for an additional 2 minutes until further thickened.

Transfer the filling to a bowl to cool completely.

In a small saucepan, whisk together water and flour over medium heat. Keep whisking constantly for 4–5 minutes until thickened.

Transfer the tangzhong to a bowl and let it cool to room temperature.

In a stand mixer bowl, combine flour, sugar, yeast, and salt. Add milk, egg, vanilla extract, and the cooled tangzhong. Mix until a shaggy dough forms.

Incorporate softened butter, one tablespoon at a time, mixing until fully incorporated. Knead on medium speed for about 10–11 minutes until smooth and elastic.

Shape the kneaded dough into a ball and place in a greased bowl. Cover and let rise for about 1 hour until doubled in size.

In a mixing bowl, combine melted butter, flour, brown sugar, and cinnamon until crumbly. Chill in the refrigerator.

Roll the dough into an 18×15-inch rectangle, spread cinnamon filling, followed by cooled peach jam, and layer sliced peaches.

Cut into 12 strips, roll each strip tightly, and place seam side down in a baking dish.

Cover and let rise for about an hour until puffy. Preheat oven to 325°F and sprinkle the topping over the rolls.

Bake for approximately 30–35 minutes until golden brown. Allow to cool slightly before serving.

In a mixing bowl, combine cream cheese and softened butter until smooth. Gradually add powdered sugar and then drizzle in heavy cream to achieve desired consistency.

Drizzle the cream cheese frosting over the warm rolls before serving.