Preheat the oven to 350°F/175°C and line and grease a 9×9 inch square pan. Grate the carrots using the fine side of your grater.
2 cups finely grated carrots
In a medium-sized bowl, add in flour, baking soda, baking powder, cornstarch, cinnamon, and salt. Mix together and set aside.
1 3/4 cups all-purpose flour, 2 tbsp cornstarch, 3/4 tsp baking soda, 3/4 tsp baking powder, 1/4 tsp salt, 1 1/2 tsp cinnamon
In a large bowl, add brown sugar and orange zest. Rub together with your fingers for about a minute. This will help release the flavours of the orange.
3/4 cups dark brown sugar, zest of 1 orange
Whisk in the oil. Then whisk in the eggs and vanilla for 2-3 minutes. Then whisk in the sour cream.
2 large eggs, 1 tbsp vanilla, 2/3 cups oil, 1/2 cup sour cream
Whisk in the grated carrots.
2 cups finely grated carrots
Add the dry ingredients in and gently using a spatula, mix until just combined.
Transfer into the prepared pan and spread evenly. Sprinkle streusel evenly on top. Bake for 45-55 minutes or until a toothpick inserted in the middle comes out clean (mine took 50 minutes exactly).
This carrot coffee cake is so delicious! It's best served fresh or the next day, you can leave it on your counter for up to 3 days or in the fridge for a week!