Add potatoes to a small saucepan and fill with enough water to cover the potatoes. Bring to a boil over medium-high heat and cook until the potatoes are fork tender.

Once cooked, remove from the heat and drain, reserving 1⁄2 cup of the potato water. Mash the potatoes, then set aside to cool.

In the bowl of a stand mixer fitted with a whisk attachment combine warm milk, yeast and sugar. Lightly whisk together, then let proof for 5 minutes, until bubbly.

Once proofed, swap the attachment to a dough hook and add in bread flour, all purpose flour and salt. Mix until combined - the texture will be clumpy and sandy.

Add in potato water and mix, then add in potatoes, shortening and butter. Knead until the mixture comes together - the texture will seem dry, but just trust the process! Continue kneading the dough on medium speed for about 10-15 minutes. The dough will be ready when it is able to be stretched out without breaking.

Form the dough into a ball, then place into a large greased bowl. Cover with plastic wrap or a clean kitchen towel and let rise for 1 hour, or until doubled in size.

Once risen, punch down the dough, then turn out onto a clean, lightly floured surface. Press the dough out into a rectangle, as even as possible. Cut into 16 even squares. Roll each dough piece and pinch together and roll until smooth.

Place the rolled dough pieces into a greased 9x13” baking dish. Lightly cover, then let rise for 45 minutes - 1 hour. Towards the end of the rise time, preheat the oven to 350°F.

Once risen, place the rolls into the preheated oven on the center rack. Bake for 20 to 25 minutes, until golden brown and baked through.

Once baked, remove from the oven. Serve while warm. Can brush tops with butter if desired.