4tablespoonsunsalted buttercut into 1/2-inch pieces and chilled
1cuppecansalmonds, or walnuts, chopped
1 ¾cupsour creamabout 16 ounces
1cuplight brown sugar
7tablespoonsunsalted buttermelted and cooled
For the streusel
Use your fingers to mix together the sugars, flour, butter, and cinnamon in a medium bowl until it resembles coarse meal. Stir in the nuts and set aside.
Coat two 9-inch cake pans with nonstick cooking spray. In a large bowl, mix together the flour, baking powder, baking soda, cinnamon, and salt.
In a separate bowl, whisk the sour cream, sugars, eggs, and melted butter together until smooth. Gently whisk the egg mixture into the flour mixture until smooth and well combined, but do not over mix.
Scrape the batter into the prepared pans and smooth the tops. Sprinkle the streusel evenly over the top of both cakes.
Wrap the pans tightly with plastic wrap and refrigerate for up to 24 hours or freeze for up to 1 month.
Preheat oven to 350°F/175°C. Unwrap the cakes and bake until the tops are golden and a toothpick inserted into the center comes out with just a few crumbs attached, 25-30 minutes if baking right away, 30-35 minutes if refrigerated, or 40-45 minutes from frozen (do not thaw first). Let cool on a wire rack for 15 minutes before serving.
Do not try to put all of the batter into one large cake pan because it will not bake evenly.