Position a rack in the center of the oven and preheat the oven to 375°F. Spray a 9x5x3-inch metal loaf pan with nonstick spray.
Whisk the flour, baking powder, baking soda, salt, cinnamon, cloves, ginger, and nutmeg in a medium bowl to blend. Using an electric mixer, beat the pumpkin, buttermilk, sugar, oil, and orange zest in a large bowl until blended. Mix in the eggs. Beat the cereal into the batter, then add the flour mixture and mix just to blend. Transfer the batter to the prepared pan and smooth the top, then sprinkle with sliced almonds and press them in lightly to adhere.
Bake the bread until a tester inserted into the center comes out clean, about 1 hour and 10 minutes. Transfer the pan to a rack and cool for 10 minutes. Turn out the bread onto the rack, then invert the bread nut side up and cool completely.