In a small bowl, combine the water and yeast. Let it sit until the yeast foams, about 5 minutes.

Meanwhile, melt the butter in a small pot. Add the pineapple juice and milk and heat until it reaches 110ºF. (If it gets hotter than that, set it aside until it has cooled to 110ºF - 115ºF so that you don’t risk killing the yeast.)

In a large bowl, or the bowl of a stand mixer, combine 4 cups of the flour, the potato flakes, sugar, and salt.

Add the butter mixture to the bowl, followed by the yeast mixture. Mix to combine.

Add the eggs, mix, then add the vanilla. Start adding the remaining flour, 1/2 cup at a time, until it starts to come together. Switch to the dough hook and continue to knead for about 5-6 minutes, adding flour as needed, until the dough is soft and smooth - it will still be tacky, but shouldn’t be overly sticky. (Alternately, turn the dough out onto a surface and knead, adding flour as needed, until smooth and soft.)

Spray a large bowl with nonstick cooking spray. Add the dough, and turn once to coat. Cover and let rise until the dough has doubled, about 1 1/2 hours.

Once the dough has risen, punch it down and turn it out onto a lightly floured surface. Divide the dough into 3 equal portions. If making round boules, shape into balls and place in 9-inch pans that have been lined in parchment paper. If making loaves, shape and place in 9x5-inch loaf pans. Cover and let rise again until doubled, about 45 minutes.

Preheat the oven to 350ºF. Bake the loaves until golden brown, about 30-35 minutes. If the bread starts to become too dark, cover lightly with foil in the last 10-15 minutes.

If desired, rub the loaves with butter as soon as they come out of the oven. Let cool before slicing.