Heat oven to 325°. Prepare two loaf pans (9-inch x 5-inch) OR six small loaf pans (3-inch x 5-inch) and spray with cooking spray or Baker's Joy (cooking spray + flour).
In a large bowl, add granulated sugar, oil, and eggs. Mix together with a wire whisk until combined and smooth. Add the applesauce and buttermilk. Mix together until combined.
Add the flour, cinnamon, baking soda, salt, and baking powder. Stir together with a spatula or wooden spoon just until combined and no flour streaks remain.
Divide batter evenly between the prepared pans. Each loaf pan should be a little over halfway filled with batter.
To make the streusel topping combine all ingredients into a small bowl. Use your hand or a small spoon to mix it all together until it forms a crumb mixture. Sprinkle over top the batter in the loaf pans.
** To get butter soft & slightly melted, microwave for 35 seconds and then add it to the streusel mixture.
Cook the large loaf pans for 60-70 minutes (mine was done at 60 minutes) OR cook the small loaf pans for 30-40 minutes.
** You may want to loosely lay a piece of tin foil over the bread during the last 15 minutes of cook time to prevent over browning.
Let cool in the loaf pan for at least 30 minutes. Serve warm or at room temperature. Extras can be stored, covered, at room temperature.