Preheat the oven to 350F (180C).
Butter an 8″ (20cm) square cake pan and line with parchment paper.

In a small bowl, mix 2 tablespoons of sugar, 2 teaspoons of cinnamon, and the coffee powder. Set aside.
In a large bowl, combine the flour, sugar, baking powder, remaining cinnamon, and salt.
In a medium bowl, beat together the milk, eggs, vanilla, and melted butter.
Pour into the flour mixture and stir until smooth.

Pour half of the batter into the prepared pan and spread evenly. Sprinkle the sugar-cinnamon-coffee mixture and mini chocolate chips.
Then spread the remaining batter evenly.

Bake for 35-40 minutes or until a toothpick inserted comes out clean. Let the cake cool in the pan for 15 minutes, then invert onto a wire rack and remove the parchment paper.
Let cool completely before glazing.

For the glaze:
Melt the chocolate and butter together in a double boiler and stir until smooth. Spread over the top of the cake and smooth with a spatula.
Cut into squares and serve.