1 1/4 cups coarsely chopped walnuts, divided
1 1/2 cups white whole-wheat flour (see Note)
1/2 cup barley flour (see Note)
2 teaspoons baking powder
1 teaspoon ground cinnamon
3/4 teaspoon ground cloves
1/2 teaspoon baking soda
1/4 teaspoon ground nutmeg
1/4 teaspoon salt
2 large eggs, at room temperature
3/4 cup packed dark or light brown sugar
2/3 cup low-fat Greek yogurt
2 teaspoons freshly grated orange zest
1/2 cup orange juice
1/4 cup extra-virgin olive oil
SYRUP
1/3 cup orange juice
1/4 cup packed dark or light brown sugar
1 small strip orange zest (1-by-1-inch)
2 whole cloves