Whisk the warm milk, water, yeast, and honey in the bowl of a stand mixer fitted with a dough hook or paddle attachment. Cover and allow to sit for 5-8 minutes until the mixture is foamy. Note: if using instant yeast, you don't need to wait; just go to the next step.
Add all-purpose flour (or bread flour) and whole wheat flour; mix on low speed until the dough pulls away from the bottom of the bowl and a dough forms, about 3 - 4 minutes. Note: if using instant yeast, you need to add the yeast along with the flours.
Add butter; mix until incorporated, about 2 - 3 minutes. Then, increase the speed to medium and continue kneading the dough on low speed for 5-8 minutes until smooth and pliable. Note: If you do not have a stand mixer, you can mix this dough with a large wooden spoon or rubber spatula and then knead with your hands over a clean surface. It will take a bit of arm muscle, but it's doable.
Lightly grease a large bowl with oil or nonstick spray. Place the dough in the bowl. Cover and let rise for 1-2 hours in a warm place, or until double in size. When the dough is ready, punch it down to release the air.
After the dough has doubled in size, dust your work surface with a bit of flour and turn the risen dough out; gently punch it down to release the air. Divide the dough into 16 pieces. Shape each piece into a smooth ball. I do this entirely with my hands, so take one piece and just roll the dough against the counter until round and smooth.
Grease a large baking sheet.
Place the balls on the prepared baking sheet, cover them, and let them rest, in a warm place, for 30 minutes or until puffy.
Preheat oven to 425º F (218º C).
Brush each roll generously with whole milk, then sprinkle with sesame seeds and pretzel salt, if desired.
Bake for 20 minutes until the rolls are golden brown and baked through. Remove them from the oven, and transfer them to a rack to cool. Optional: Brush the tops of the rolls with melted butter for a softer, richer flavored crust.