In a small bowl, whisk together the sugar, flour and cinnamon.
Add in the diced butter (it is best to use cold butter). With your hands or a pastry blender work the butter into the flour mixture. It will begin to look sandy, with some slightly larger clumps.
Stir in the chocolate chips and set aside.
For the Donuts:
Preheat the oven to 350 degrees Fahrenheit. Lightly grease the donut molds.
Whisk together the flour, sugar, baking powder, salt and cinnamon.
In a separate bowl whisk together the oil, milk and egg.
Add the wet ingredients to the dry ingredients and gently combine. Then add in the chocolate chips.
Divide the batter between 12 donut molds. Top with crumb topping. Bake for 14-15 minutes or until a toothpick inserted into one comes out clean.
Allow to cool for 5 minutes in the pan, then remove to a cooling rack.
Notes
The calories shown are based on the recipe making 12 donuts, with 1 serving being 1 donut. Since different brands of ingredients have different nutritional information, the calories shown are just an estimate. **We are not dietitians and recommend you seek a nutritionist for exact nutritional information.**