Serves 12. Adapted slightly from Cooking Light Quick Baking.
1-1/2 cups unbleached all-purpose flour
1 cup granulated sugar
1-1/2 tsp baking powder
1-1/2 tsp ground cinnamon
1/8 tsp ground cloves
1/2 tsp kosher salt
3/4 cup nonfat or 1% milk
2 Tbsp butter, melted
1 tsp pure vanilla extract
1 large egg, lightly beaten
1 cup diced peeled Granny Smith apple (1 large apple)
For the streusel topping:
1/4 cup packed light brown sugar
2 Tbsp unbleached all-purpose flour
1/2 tsp ground cinnamon
2 Tbsp chilled butter, cut into small pieces
Preheat oven to 350°F. Spray an 8x8 or equivalent size loaf pan with baking spray, and set aside.
In a large bowl, whisk together the flour, granulated sugar, baking powder, 1-1/2 tsp ground cinnamon, cloves and salt. Make a well in the center. In a 2-cup or larger glass measuring cup, whisk together the milk, melted butter, vanilla and egg. Pour the mixture into the well in the flour, and use the whisk to combine just until all of the dry ingredients are moistened. Then, using a rubber spatula, fold in the chopped apple. Pour the mixture into your prepared pan, and set aside.
In a large bowl, combine the streusel ingredients. Using a pastry blender or two knives, cut the butter into the dry ingredients until it's the consistency of coarse meal. Sprinkle the streusel evenly over the cake batter.
Bake at 350F for 45 minutes, or until a wooden toothpick inserted in the center comes out clean. Cool in the pan on a wire rack for at least 10 minutes before serving, and serve warm; or, cool completely in the pan and freeze.