Ingredients

1 1/2 sticks (3/4 cup) unsalted butter, room temperature, plus more for pan 

1 1/4 cups all-purpose flour 

3/4 cup barley flour, such as Arrowhead Mills 

1 1/2 teaspoons baking powder 

1/2 teaspoon coarse salt 

1 navel orange 

1 1/2 cups granulated sugar 

4 ounces cream cheese, room temperature 

1 teaspoon pure vanilla extract 

3 large eggs, room temperature 

1 cup confectioners' sugar 

1 teaspoon orange liqueur 

Preparation

Preheat oven to 325 degrees with rack in lower third. Butter a 9-by-5-inch loaf pan. In a bowl, whisk together flours, baking powder, and salt. With a vegetable peeler, peel zest from half of orange into about 5 strips; squeeze and reserve 2 teaspoons juice. Pulse zest strips with granulated sugar in a food processor until finely ground.

In another bowl, beat butter and cream cheese on medium until smooth. Add orange-sugar mixture; beat on high until pale and fluffy, about 5 minutes. Beat in vanilla and eggs, one at a time, on medium. Add flour mixture; beat on low until just incorporated. Pour batter into pan; smooth top with a spatula.

Bake, rotating pan halfway through, until cake is golden brown and a tester inserted in center comes out clean, 1 hour, 15 minutes. (If browning too quickly, tent with foil.) Let cool 30 minutes in pan on a wire rack. Remove from pan; let cool completely on rack, about 2 hours.

In a bowl, whisk together confectioners’ sugar, reserved orange juice, and liqueur until smooth. Spread glaze over cake; sprinkle finely grated zest from remaining orange half over top.