Note: *preheat the oven to 350 degrees. spray and paper and spray again a 13x9x2-inch baking pan. set aside.
TO MAKE THE CRUMBLE
1. Cut the butter into small cubes. set aside.
2. Place all of the dry ingredients in a medium-sized bowl and whisk to combine. Add the butter, and using your hands, incorporate the butter into the dry ingredients, until a variety of different sized crumbs form (some big, some not) and there is no more loose flour or sugar. Place the crumble in the refrigerator.
TO MAKE THE CAKE
1. Place the cranberries in a medium sized bowl and lightly spray with cooking spray. Toss with 2 tablespoons of the all-purpose flour until all of the berries are coated. Place in the freezer until ready to use. If cooking spray is not your thing, you can skip it. I call for it, as it helps the flour to stick to the cranberries, and thus prevents them from sinking.
2. Place the remaining all-purpose flour and all of the cake flour, the baking powder and salt in a medium sized bowl and whisk to combine.
3. place the butter in the bowl of a stand mixer fitted with the paddle attachment. Cream the butter on medium-high until smooth. Stop the mixer, scrape down the bowl with a rubber spatula, reduce the speed to medium, and add the vanilla, and then the sugar gradually, stopping the mixer and scraping down the bowl periodically, if needed, until all of the sugar is added.
4. Increase the speed of the mixer to medium-high and cream the butter and sugar for at least 5 minutes until quite light and fluffy, stopping and scraping, occasionally, if needed. Reduce the speed to medium, add the eggs, one at a time, scraping down the bowl after each addition.
5. Reduce the mixer speed to low, and add the dry ingredients in three installments, alternating with the heavy cream, and beginning and ending with the dry. Scrape the bowl after the second addition of the dry. Stop creaming all together when the batter still has a bit of dry flour throughout.
6. Remove the bowl from the mixer and add three cups of the cranberries. Using a rubber spatula fold the berries into the batter. Transfer the batter to the prepared pan, smoothing the top, and place the pan in to the refrigerator for 30 to 60 minutes (this stint in the fridge, also prevents the berries from sinking to the bottom of your buckle).
7. Remove the pan from the fridge and sprinkle the top with the remaining cup of cranberries. Cover the berry layer with the crumble, pinching the crumble between your fingers to form large crumbs.
8. Place the buckle in the preheated oven and bake for about 50 - 60 minutes, or until a toothpick comes out with only a moist crumb or two. Rotating the cake halfway through the baking time.
9. Let the cake come to room temp before slicing it and serving. Or don’t and serve it warm with a dollop of whipped cream. The cake is very moist and will last on the counter for a few days, tightly wrapped. The slices also freeze well and can be reheated in a 350-degree oven, wrapped in tinfoil.
Note on Sinking Berries:
When making this buckle, I had some berry-sinking issues. That is why I recommend freezing the cranberries, spraying and flouring them, placing the batter in the fridge to chill before baking, and why I have you sprinkle a cup of the berries right underneath the crumble.