In the bowl of a stand mixer, fitted with a whisk attachment, combine the flour, granulated sugar, brown sugar and yeast.
Swap the attachment to a dough hook and add in the pineapple juice, eggs and vanilla. Knead together until a rough dough forms.
Add in the butter and shortening and knead on medium speed for 7 minutes, until a soft dough forms.
Once the dough has been kneaded, roll it into a ball. Transfer the dough into a separate, greased bowl. Spray the top of the dough with baking spray, then cover with plastic wrap or a clean kitchen towel. Let the dough rise for 1 hour, or until doubled in size.
Once the dough has doubled in size, transfer it to a clean, lightly floured surface. Press out with your hands or use a rolling pin to roll the dough into a 9x11” rectangle. Use a pizza cutter to cut the dough into 12 equal squares. Fold each corner of the square into the center, then repeat that a second time with the folded corners.
Next, roll the dough into a smooth ball. Repeat with the remaining dough pieces. Once all of the dough pieces are rolled, allow them to set for 15 minutes to rise.
Once the rolls have risen for 15 minutes, punch them down and press them out flat, then re-roll them up tightly. Place the rolls into a 9x13” baking dish that has been buttered. Lightly cover with plastic wrap or a clean kitchen towel, then let them rise for 30-45 minutes. Not quite doubled in size.
Preheat the oven to 350°F. Towards the end of rise time, prepare the egg wash by adding the egg, milk and salt in a small bowl. Whisk together to combine.
Once the rolls have risen, brush them with the egg wash, then place them into the preheated oven. Bake for 28 minutes, until golden brown.
Once baked, remove from the oven and immediately brush with melted butter. Serve immediately or cover the pan with tin foil for 20 minutes to make the rolls extra soft!
The rising times for the dough will vary depending on the temperature of your kitchen. It may be a little more or less than the listed time. For best results, use the dough as soon as it reaches the instructed size.
If not consumed fresh, heat the rolls for 5-10 seconds in the microwave to soften and freshen up.
Shortening - Melted butter may be used instead.
Unsalted butter may be used instead. If used, add 1⁄8 tsp of salt to the dough recipe.