Ingredients

• Nonstick vegetable oil spray
• 4 1/4 cups all-purpose flour, plus extra for dusting pans
• 1 3/4 cups packed light or dark brown sugar
• 1 1/2 cups sugar
• 2 tablespoons ground cinnamon
• 1 tablespoon ground nutmeg
• 3/4 teaspoon salt
• 1 1/2 cups grape-seed oil
• 1 tablespoon baking soda
• 1 1/2 tablespoons baking powder
• 3 large eggs
• 1 1/2 cups buttermilk
• 8 mini (5- by 3-inch) loaf pans

Instructions

1. Preheat the oven to 350°F. Spray 8 mini loaf pans with nonstick vegetable oil spray then dust the pans with flour, tapping out any excess.
2. In a large bowl, whisk together the flour, light or brown sugar, sugar, cinnamon, nutmeg, and salt. Drizzle in the grapeseed oil then whisk until the mixture resembles wet sand. Measure out 1 cup of the mixture and reserve it for the topping.
3. Add the baking soda and baking powder to the large bowl and stir with a spatula to combine. Add the eggs and stir to combine then add the buttermilk and stir to combine—the batter will have some lumps. Scoop about 1 cup of batter into each of the prepared pans, smoothing the tops. Sprinkle the reserved topping in very small clumps over the top of each cake and bake until a wooden toothpick inserted in the center comes out clean, 30 to 35 minutes. Transfer to a wire rack to cool completely, then invert onto the rack to unmold. DO AHEAD: Coffee cakes can be baked in advance, cooled, covered, and kept at room temperature for up to 24 hours.