Preheat the oven to 350° F
Rub a 9 1/2-inch fluted tart pan with olive oil. Alternately, I used a loaf pan and lined it with parchment paper.
Sift the dry ingredients into a large bowl, pouring any bits of grain or other ingredients left in the sifter back into the bowl. Set aside.
In another large bowl, whisk the eggs thoroughly.
Add the olive oil, milk, and rosemary and whisk again.
Using a spatula, fold the wet ingredients into the dry, gently mixing just until combined.
Stir in ⅔ of the chocolate.
Pour the batter into the pan, spreading it evenly and smoothing the top.
Sprinkle with the remaining chocolate and run a fork along the length of the chocolate so that the batter envelops it just a bit.
Sprinkle with the natural sugar.
Bake for about 40 minutes, or until the top is domed, golden brown, and a skewer inserted into the center comes out clean.
My cake, in the loaf pan, took closer to 50-55 minutes.
Also, just when the cake was nearly finished baking, if I want a bit more color on top, I'll finish it off under the broiler for a minute. This will caramelize the sugar on top and gave it a bit of crunch. (Don't walk away from the cake while it is under the broiler)
The cake can be eaten warm or cool from the pan, or cooled, wrapped tightly in plastic, and kept for 2 days