In a large bowl, mix 1 tsp of the honey in 1/4 cup of the warm water and add the yeast. Let sit for 5 to 10 minutes. Once foaming and bubbling, add in the rest of the honey, the butter, salt, the rest of the warm water, and 3 cups of the white whole wheat flour. Mix on low with a handheld mixer until combined, then raise speed to medium for 2 to 3 minutes, scraping the bowl occasionally. Mix in remaining white whole wheat flour.
Scrape the bowl then stir in 2 1/2 cups of the all-purpose flour until dough pulls away cleanly from the bowl.
Lightly flour a work surface and knead in remaining 1/2 cup all-purpose flour gradually, until dough is springy and elastic, about 8 to 10 minutes. Lightly oil a large bowl and place dough in bowl, then flip dough over to coat both sides. Cover with a kitchen towel and let rise until doubled in size, usually about 30 to 40 minutes, longer if in a cool place.
Grease or spray two 9x5-inch loaf pans. Punch down the dough and then divide in half. Let rest for about 10 minutes then shape each half into a loaf and place in pans. Cover and let rise again until doubled in size, usually about 30 to 40 minutes.
Preheat oven to 375°F. Bake loaves uncovered for 25 minutes. Reduce oven temperature to 350°F and bake an additional 20 to 25 minutes, or until loaves sound hollow when knocked on the bottom. (Tip: brushing butter on top of the bread upon removal from the oven will help prevent a hard crust.) Immediately transfer loaves from pans to cooling racks, and let cool entirely before serving, usually about an hour.
Loaves can be stored in the freezer for up to three months.