In the bowl of a stand mixer, whisk together the yeast and 60 mL of warm water. Let this sit for a few minutes until it is foamy.
Add in the whole wheat flour, bread flour, salt and water. Use the hook attachment of the mixer to mix the dough on medium-high speed for 10-15 minutes. This process will take a while, so don't worry! You will know the dough is ready when you can pull and stretch it from the hook. It should feel elastic and firm. If your dough needs a bit of help getting there, put the mixer on high speed for the last 1-2 minutes.
Lightly oil the sides of a large bowl. Add the dough to the bowl, loosely cover it with a lid or towel, and let it rise in a warm place for about 1 hour or until it is doubled in size.
When the dough is ready, pour almost all of the olive oil in a 10" cast iron pan, or a 9"x11" rimmed baking sheet. Add the dough to the pan. Lightly stretch it with your hands until it reaches the edges. Cover the dough with either a lid (leaving a loose crack if you do this) or oiled cling wrap. Let it proof another hour or until it has risen about 50% in size.
When the dough has about 20 more minutes of rising time left, preheat the oven to 425°F.
When the dough is ready, drizzle the remaining olive oil over the top. Use your hands to "dimple" the dough, forming your fingers into a claw-like shape and pressing into the dough, gently pressing in indents. Do this all the way down the pan.
Sprinkle the flakey salt on top of the dough, and then bake at 425°F for 25-28 minutes.
Remove from the oven when it's golden brown, and serve fresh!