Preheat oven to 350 degrees Fahrenheit.
In a large mixing bowl, whisk vegetable oil and sugars together.
Stir in eggs, milk, sour cream, and vanilla until just combined.
Add dry ingredients to wet ingredients by first sprinkling on flour, baking powder, salt, cinnamon, and nutmeg. Gently stir until just combined. Do not overmix.
Spoon batter into well-greased muffin tin until ⅔ full.
Make cinnamon sugar topping by stirring together sugar, cinnamon, flour, and butter.
Sprinkle cinnamon sugar topping generously over each muffin top.
Bake in the oven for 20-25 minutes or until a toothpick comes out clean.