In a small bowl, mix warm milk, 1 tbsp sugar, and yeast. Let sit 5–10 minutes until foamy.
In a large bowl, whisk pineapple juice, melted butter, egg, remaining sugar, vanilla, and salt. Add yeast mixture.
Gradually add flour, mixing until a soft, slightly sticky dough forms. Knead 8–10 minutes by hand or 5–7 minutes with a stand mixer.
Place dough in a greased bowl, cover, and let rise in a warm spot for 1–1½ hours until doubled.
Punch down dough, divide into 15 pieces, shape into balls, and place in a greased 9x13-inch baking dish.
Cover and let rise 30–45 minutes until puffy. Preheat oven to 350°F.
Optionally, brush with egg wash. Bake 20–25 minutes until golden brown.
Cool slightly before serving.