Measure water and milk into a microwave-safe bowl; heat 30 to 45 seconds until warm (about 115 degrees F). Alternatively, you could heat the milk and water on the stovetop in a small saucepot. Pour warm milk mixture into the bowl of a stand mixer.

Whisk in the yeast and honey. Let sit 10 minutes until yeast is foamy.

Add all-purpose flour, whole wheat flour, oats, butter and salt to the bowl of the stand mixer. Fit with the dough hook attachment and mix on low speed until all the ingredients have combined.

Increase to medium speed and knead 6 minutes until dough is smooth, elastic and only slightly sticky.

Keep dough in the stand mixer bowl or in a clean mixing bowl, and cover with a tea towel. Let rise 1 hour until doubled.

When dough has doubled transfer it to a lightly floured surface. Turn the dough out onto a lightly floured surface. Fold each of the four sides towards you into the center, turning the dough after each fold. This will create a little packet. Flip the dough so the seam is on the counter. Shape it into a round by using both hands to pull the dough towards you. Once you have a round ball with a smooth top, cover to keep the top from drying out and allow it to sit and bench rest for 15 minutes.

We are going to shape this loaf into a log. Take the dough round and flip it over so the seam is facing up. Grab the top and bottom edges and gently pull it into a small rectangle. Place it on the counter and fold the top edge down 2/3rd of the way and press it into the dough. Rotate so that the unfolded edge is now away from you and fold that edge down towards you to meet the bottom edge. Press to seal. Now we are going to do 2 thumb folds. Take the top edge with your right hand and fold it over you thumb about half way down, pressing to seal as you go. Repeat until you have folded the entire length. You will notice the dough getting tighter and also longer. Repeat the thumb fold once more, sealing really well on the bottom. You should now have a log shape that is even in width along the whole length, that is the length of your pan, and tight enough to not slouch onto the counter.

Transfer the shaped dough to a lightly greased 9-by-5-inch loaf pan, seam-side down. Cover with a tea towel and let rise 30 to 40 minutes until dough reaches the edges of the pan (but not doubled).

While the loaf final proofs, preheat the oven to 375°F . Sprinkle oats on top of risen loaf. Bake 35 to 45 minutes, rotating halfway through baking, until loaf is golden brown on top and reads 185°F on an instant read thermometer inserted into the center.

Remove from loaf pan and transfer to a cooling rack to cool completely.