Preheat and prep. Heat the oven to 350°F (175°C). Grease a 10-inch cast-iron skillet with butter or oil. If you don’t have cast iron, use a 9-inch round cake pan.

Mix the dry ingredients. In a large bowl, whisk 1 cup gluten-free all-purpose flour, 1 cup almond flour, 1 teaspoon baking soda, 1/2 teaspoon fine sea salt, 2 teaspoons ground ginger, 1 teaspoon cinnamon, and a pinch of nutmeg.

Whisk the wet ingredients. In a second bowl, whisk 2/3 cup molasses, 1/2 cup brown sugar, 2 large eggs, 1/2 cup plain yogurt or sour cream, 1/3 cup neutral oil, and 2 teaspoons vanilla. Add 1 teaspoon orange zest if using.

Combine gently. Pour the wet ingredients into the dry. Stir with a spatula until just combined. The batter will be thick and glossy. Don’t overmix.

Fill the skillet. Scrape the batter into the prepared skillet and smooth the top. If you like, sprinkle a tiny pinch of coarse sugar over the surface for sparkle.

Bake. Place the skillet on the middle rack and bake 22–28 minutes. It’s done when the center springs back, the edges pull slightly from the pan, and a toothpick comes out with a few moist crumbs.

Cool briefly. Let the cake rest in the skillet for 10–15 minutes. This helps it set and makes slicing cleaner.

Serve. Dust with powdered sugar if you like. Cut into wedges and serve warm with whipped cream, a dollop of yogurt, or vanilla ice cream.