Use a spatula to scrape up the bottom and sides of the bowl. Sprinkle 1/3 of the streusel at the bottom of the bundt cake pan, then pour half the batter on top. Smooth to cover the streusel.
Grease and flour a large (10 or 12-cup) bundt pan and set aside. In a large mixing bowl, stir together the cake and pudding ... stir together the streusel ingredients: granulated sugar, cinnamon ...