Preheat your oven to 400 degrees Fahrenheit. Lightly spray a baking sheet with cooking spray and set aside.
In a medium bowl, toss sliced strawberries with balsamic vinegar, extra virgin olive oil, honey and salt until all strawberries are coated. Transfer strawberries to your prepared baking sheet, spreading them out in an even layer, and bake for 20 minutes.
While strawberries are roasting, prepare your cake batter. Lightly coat a 10-inch cast iron skillet in olive oil and set aside.
In a large bowl, sift together flour, sugar, and baking powder. Add salt and cinnamon and whisk to combine.
In a separate medium bowl, beat together buttermilk, olive oil, eggs and vanilla with a wire whisk until fully combined. Add wet ingredients to the dry ingredients and mix with a rubber spatula until just combined.
Once strawberries are done, lower the oven temperature to 350 degrees.
Pour cake batter into prepared cast iron skillet. Top batter with roasted strawberries and some of the roasting liquid, being sure to spread strawberries out over the top of the cake batter. Bake cake at 350 degrees for 45-55 minutes, until a toothpick inserted into the center comes out clean aside from a few moist crumbs.
Allow cake to cool completely in the skillet on top of a wire rack. Top cake with fresh sliced strawberries and powdered sugar if desired and enjoy!