In the bowl of a stand mixer (or just a large bowl), add the yeast and 500 grams of the water. If using active, not instant, yeast, let sit until bubbly, 5-15 minutes. If using instant yeast, continue to the next step.
Add the flours, honey, olive oil, and salt.
If mixing by hand, mix together and then knead for 10 minutes. If using a stand mixer, mix on low for 3-4 minutes and then 10 minutes on medium. IMPORTANT: depending on humidity, you may need up to another 50-60 grams of water, added a tablespoon at a time, to get a nice cohesive dough. Should be a tad sticky but not slack.
Weigh and put in a lightly-greased bowl and let rise at room temperature for 60-120 minutes until doubled. Check after 30 to give you an idea of how it's going. Rose very fast for me and was ready for the next step at 60 minutes.
Pour out onto a lightly floured surface and punch down. Divide into two equal pieces. (Should be about 690 grams each one.) Flatten a piece into a rectangle, fold into thirds onto itself, then turn and rotate into a log, tucking the ends under. Place into a well-greased loaf pan, cover, slash the tops, and let rise another 30-90 minutes until doubled. In fact, even before fully doubled as you'll need to warm your oven.
Heat oven to 375°F / 190°C.
Place loaves on the center rack and bake for 30-35 minutes until browned. A thermometer in the center should register 190°F / 88°C.
Turn loaves out of loaf pans onto wire racks and put racks into the oven. Turn oven off and prop door open slightly so that the bottoms of the loaves can brown and the outside can bake better. (I find loaves done in loaf pans like this to be a bit "soggy" on the outside if you don't get them out of the pan immediately.)
Let rest at least an hour before slicing and serving.