In a small saucepan, whisk together 1/4 cup of water and 1/4 cup of bread flour. Cook over medium heat until thickened (about 3-5 minutes). Let cool.

Combine 3 ⅔ cups bread flour, ⅓ cup sugar, 2 teaspoons yeast, and 1 teaspoon salt in a stand mixer bowl. Add heavy cream, whole milk, egg, and cooled tangzhong. Mix until a rough dough forms.

Gradually add 6 tablespoons softened butter. Knead for 8-10 minutes on medium speed until smooth and elastic.

Shape dough into a ball, place in a greased bowl, cover, and let rise for about 30 minutes.

Mix ⅔ cup packed brown sugar, 2 tablespoons cinnamon, and 4 tablespoons softened butter in a medium bowl until creamy. Set aside.

In a saucepan, combine ½ cup sugar, 2 tablespoons butter, and a pinch of salt. Heat until caramelized (about 5-7 minutes). Let cool slightly.

Prepare a 9x13-inch baking pan with parchment paper. Drizzle caramel and arrange pineapple rings and cherries.

Roll out dough into a 15x21 inch rectangle. Spread filling evenly, leaving a half-inch border.

Slice into twelve strips and roll each tightly. Place rolls in the prepared pan.

Cover the pan and let rolls rise in a warm place for about 1-2 hours until doubled in size. Preheat oven to 325°F (162°C).

Bake for 35-40 minutes until golden brown, checking for an internal temperature of 185°F.

Cool rolls in the pan for 20 minutes. Whisk together icing ingredients and drizzle over warm rolls.

Flip the pan onto a lined baking sheet to release rolls.