Use a paper towel to generously oil the inside of your cast-iron skillet.
Place the skillet on the middle rack in your oven and preheat to 400°F / 200°C.
In a large bowl, add the cornmeal, pastry flour, Sucanat, baking powder, and sea salt. Gently whisk to combine.
Add the egg, olive oil, milk, and yogurt to the dry .
Mix with a spatula until just combined—do not overmix.
Once the oven reaches temperature, use an oven mitt to carefully slide the middle rack out.
Pour the batter into the hot skillet (it should sizzle!)
Slide the rack back into the oven and bake until the cornbread is golden brown and firm to the touch, about 25 to 30 minutes.
Remove from the oven and let it cool for a few minutes before slicing into wedges and serving warm.