Preheat oven to 350°F. Spray a 9x13-inch baking pan with nonstick spray. Set aside.
Combine the streusel ingredients together and set aside until ready to use.
½ cup dark brown sugar, ½ cup chopped toasted sugared slivered almonds, 1 teaspoon ground cinnamon
Mix together cake mix, pudding mix, oil, 7UP, and vanilla. Add eggs one-at-a-time and mix well.
15.25 ounces yellow cake mix, 3.4 ounces Instant Vanilla Pudding mix, ¾ cup canola oil, ¾ cup 7UP® lemon-lime soda, 1 teaspoon pure vanilla extract, 4 large eggs
Pour about half of the batter into the prepared pan.
Sprinkle half the streusel mixture over the batter and swirl it through the batter with a table knife.
Pour the last half of the batter on top.
Sprinkle the batter with the last half of the streusel mixture and swirl it throughout the batter.
Sprinkle the top with extra almonds or pecans.
Bake in the preheated oven for 40-50 minutes or until a toothpick inserted in the middle comes out clean.
Remove the cake from the oven and set it on a cooling rack to cool.