Heat the oven to 360°F (182°C). Line a 9×5-inch metal loaf pan with parchment, leaving overhang for easy lifting.
In a large bowl, whisk together almond flour, oat flour, baking powder, baking soda, salt, and cardamom until evenly combined.
Prep the cranberries: Roughly chop 1/2 cup; leave 3/4 cup whole for the batter and reserve the remaining 1/2 cup for the top. Toss the chopped cranberries with 1 teaspoon of the whisked dry mixture to help keep them suspended in the batter.
Make the orange base: Place the quartered orange (trimmed ends on) in a blender with the maple syrup and vanilla. Blend until mostly smooth with tiny zest flecks, about 20–30 seconds. With the blender on low, add the 2 eggs and the yolk and blend just 10 seconds more to combine without whipping too much air.
Pour the orange mixture into the dry ingredients and fold with a spatula until no dry pockets remain. Gently fold in the floured chopped cranberries and the 3/4 cup whole cranberries.
Assemble in the pan: Spread half the batter in the pan. Scatter half of the reserved cranberries over it. Add the remaining batter, then nestle the last cranberries on top. Sprinkle the turbinado sugar evenly over the surface.
Bake for 55–65 minutes, until deeply golden and a skewer inserted in the center comes out clean or with just a few moist crumbs. If the top is browning too quickly, tent loosely with foil after about 40 minutes.
Cool in the pan for 15 minutes, then lift onto a rack. For a glossy finish, brush the warm top with the warmed maple syrup (optional). Let cool 45–60 minutes more before slicing with a serrated knife.
Practical tip: If your orange has very thick white pith or tastes bitter, trim away a little of the pith from the quarters before blending to keep the loaf bright and sweet.