The Best Gluten Free Chocolate Cake {or cupcakes}

potato starch

sorghum flour

brown rice flour

sugar

(plus 2 tablespoons cocoa powder, preferably dutch process)

baking soda

kosher salt

sour cream

light flavored olive oil

water (room temperature)

plain white vinegar

vanilla

egg

Salted Caramel Frosting (If you make the frosting in advance and store it in the refrigerator, give it several hours to return fully to room temperature again before frosting the cupcakes.)