Banana Nut Scones with Maple Glaze

mashed bananas (about 2 large ripe bananas)

plain Greek yogurt (or any plain yogurt or sour cream)

packed light or dark brown sugar

large egg

pure vanilla extract

and 1/2 cups (312g) all-purpose flour, spoon & leveled

 and 1/2 teaspoons baking powder

ground cinnamon1

salt

butter, frozen

for brushing: 3 Tablespoons (45ml) milk