Pecan Topping: In a medium bowl, combine the brown sugar, flour, and cinnamon. Add the butter and, using your fingertips, pinch the ingredients together into a sandy, crumbly mixture. Add the pecans and mix.
Preheat the oven to 350 degrees. Butter a 9 by 9-inch cake pan. In a mixer fitted with a paddle attachment (or using a hand mixer), cream the butter until smooth. With the mixer running, slowly add the sugar and mix. Add the eggs and mix until light and fluffy. Sift the flour, baking soda, baking powder, and salt together. Working in batches, add them to the butter-sugar mixture, alternating with dollops of sour cream. Mix in the raisins. Pour the batter into the prepared pan. Sprinkle the topping mixture over the cake. Bake until risen and browned, about 45 minutes. Let cool 10 minutes in the pan. Serve in squares.
Courtesy of Gale Gand, "Butter Sugar Flour Eggs" by Gale Gand, Rick Tramonto, Julia Moskin, Clarkson N. Potter Publishers, 1999