Spiced Brown Sugar Pecan Coffee Cake

For the spiced pecan crumb topping:

1/4 cup light brown sugar
1/4 cup granulated sugar
1/2 cup unbleached all-purpose flour
1/2 teaspoon ground cinnamon
1/2 teaspoon ground mace
1/2 teaspoon ground ginger
6 tablespoons (3/4 stick) cold unsalted butter, cut into small pieces
2 cups (8 ounces) pecans, coarsely chopped

For the coffee cake:

4 tablespoons (1/2 stick) unsalted butter, at room temperature
1/2 cup packed light brown sugar
1/2 cup granulated sugar
2 large eggs
2 teaspoons vanilla
2 cups unbleached all-purpose flour
1 teaspoon baking powder
1 teaspoon baking soda
1/4 teaspoon salt
1 cup buttermilk

1. Heat oven to 350 degrees. Line the bottom of an 8-inch springform pan or a 2-inch-deep removable-bottom tart pan with parchment paper. Butter the sides of the pan.

2. Prepare the crumb topping: Combine the sugars, flour and spices in a small bowl or food processor fitted with the metal blade. Work the butter into the flour with your fingers (or process if using the food processor) until mixture forms coarse crumbs (do not overprocess or it will turn to dough). Add the pecans; mix and set aside.

3. Make the coffee cake: In a bowl using a wooden spoon, or in a heavy-duty electric mixer, beat the butter and sugars until light and fluffy. Add eggs and vanilla, beating until smooth.

4. In another bowl, combine the flour, baking powder, baking soda and salt; stir with a whisk to combine. In small batches, add the flour mixture to the butter mixture alternately with small amounts of the buttermilk. Beat hard or at high speed until batter is creamy, about 1 minute.

5. Scrape half of the batter into the prepared pan. Sprinkle evenly with half of the crumb topping. Spoon remaining batter on top and sprinkle with remaining topping.

6. Bake in the center of the oven until a wooden toothpick or a cake tester inserted in the center of the cake comes out clean, about 45 to 55 minutes (baking times vary depending on the type of pan used).

7. Remove cake from oven. Let cool in pan on a cooling rack. To serve, remove sides of pan and peel off parchment paper.