Preheat oven to 350° Fahrenheit.
In a large bowl, combine Domino® Golden Sugar and sift in dark cocoa powder. Mix to combine well. Add flour, baking soda, baking powder, and salt. Whisk together well.
In another large bowl, combine Domino® Light Brown Sugar, vegetable oil, melted butter, eggs, and buttermilk. Mix well.
Pour the wet ingredients into the dry. Mix until just combined.
Add the slightly cooled espresso or strong coffee and mix until just combined.
Spray mini bundt pan generously with nonstick cooking spray and gently brush excess oil off with a brush.
Fill each cavity 2/3 of the way with the cake batter.
Bake for 16-18 minutes, until a skewer inserted comes out clean.
Let cakes cool in the pan for 10 minutes (no longer than this!)
Flip cakes over onto a cooling rack and let cool completely.