Preheat oven to 375 F degrees. Line a 12 cup muffin pan with cupcake liners.
In large bowl beat eggs with an electric handheld or stand mixer. Add 1 cup granulated sugar and beat for a minute or two until completely combined. Pour in the oil, with the beaters running, and then add the vanilla.
In a separate bowl, stir together flour, cinnamon, nutmeg, salt and baking soda.
Using a wooden spoon, mix the flour mixture into the wet mixture, a little at a time, alternating with the sour cream (or Greek yogurt).
Add the chopped apple and mix with the wooden spoon just until combined. Divide the batter between the cupcake liners.
Divide streusel topping evenly over the muffin tops, pressing it down lightly on to the batter. Brush off as much of the streusel from the area between muffins for easier cleanup.
Bake for 22 to 25 minutes, or until a toothpick inserted in the center of one of the muffins comes out clean. Remove from the oven and allow muffins to cool for about 10 or 15 minutes and then carefully remove from the muffin pan to cool completely on a wire rack.