Mix the flour, yeast, and salt using the dough hook in the bowl of a stand mixer for about 1 minute.
Combine the pineapple juice, buttermilk, melted butter, and honey in a large, microwave-safe bowl or measuring up. Blend or whisk to combine. (I like to use a small frother for this step)
Microwave the juice mixture in 30-second increments until it reaches 95-105 degrees. You can go up to 110 degrees, but anything above that will kill the yeast. I have found that 95-105 is the sweet spot for yeast.
Once the juice mixture is hot, turn the mixer on again and slowly add it to the flour mixture.
Next, add the egg and vanilla and continue mixing on low until the dough comes together. Increase the speed and mix until the dough no longer sticks to the side of the bowl. It may still stick to the very bottom of the bowl.
Working on a smooth, flat, lightly floured surface, turn the dough out and shape it into a ball. Transfer the dough ball to a lightly greased bowl. Cover with plastic wrap and a dish towel, and let it rise in a warm space for 60-90 minutes. It should double in size.
When the dough is ready, punch it down and turn it out onto a lightly floured surface. Divide it into 15 equal-sized portions. Roll them into balls and place them in a lightly greased 9x13 baking dish. Cover with plastic wrap and let rise in a warm space for another hour. They should double in size.
After the second rise, adjust the oven rack to the lower-middle position. Preheat the oven to 375 degrees.
Melt half of the honey butter and brush it over the rolls.
Bake for 10 minutes. Rotate the baking dish and bake for another 10 minutes.
If you want the tops more brown, you can broil until the rolls reach your desired color. Keep a close eye on them while broiling as burning can happen quickly.
Remove and immediately brush the tops of the rolls with more honey butter before serving.