In a medium bowl, add sugar, flour, and butter. Use your fingers to rub in the all ingredients until you get coarse crumbs. Set aside.

Preheat oven to 200C.

Line muffin tins with muffin liners.

In a large mixing bowl, sift cocoa powder, baking powder, baking soda, salt, cinnamon, and flour together.

Then combine in buttermilk, melted butter, vanilla extract, and eggs in a bowl or measuring cup.

Give it a good whisk.

Add the wet ingredients into the dry ingredients.

Mix until almost combined, then add chocolate chips.

Fold it in about 4 times. Do not over mix!

Divide batter into liner, and top with crumble mix.

Bake 15-18 minute