Make the ganache: bring 1 cup heavy cream to a simmer in a small saucepan over medium heat. Once simmering, stir in chocolate chips until smooth. Transfer to refrigerator to cool until it reaches a spoon-able consistency, about 1 hour. Once cooled, use a hand mixer to beat the mixture until it reaches soft peaks. Ganache will stiffen when returned to the refrigerator.
Make the waffle batter: Use a hand mixer to beat together butter and sugar until creamy, about 2 minutes. Add in buttermilk, egg, and vanilla extract and beat until combined. Add in flour and baking powder and mix on a low speed until just combined, scraping the sides and bottom of the bowl to make sure everything gets mixed in.
Preheat a Belgian Waffle Maker. Scoop a heaping 2/3 cup of batter onto the waffle iron. Cook waffles one at a time. Transfer cooked waffles to a wire rack to cool completely.
Assemble cake: layer the cake with at least 4 waffles, frosted with whipped ganache between each layer. Garnish with fresh berries.