Preheat oven to 325 degrees F. Grease a 9 x 13-inch pan.

In a small bowl add the brown sugar, flour, spices and pecans. Add the butter and mix until the butter is worked in and the crumble forms. Set aside.

In a medium bowl combine the pumpkin, egg, sugar, salt, and spices, with an electric mixer, process until well blended. Set aside.

In a medium bowl add the sugar and oil, beat with an electric mixer until well blended. Add the eggs mix well. Mix in the vanilla. Sift together the dry ingredients, add the dry ingredients to the egg mixture alternately with the sour cream.

To the prepared pan, spread half the batter in the bottom of the pan. Sprinkle about half the streusel over the batter. By teaspoon full drop the pumpkin filling over the streusel. Carefully spread the pumpkin filling evenly over the streusel. Drop by teaspoons of batter over the filling. Carefully spread over the filling.

Place in the preheated oven and bake for 40 to 50 minutes or until a toothpick comes out clean when inserted.