1. Preheat the oven to 350°F (175°C) and position a rack in the center. Generously grease and flour a 10- to 12-cup bundt pan, making sure to coat every ridge and corner so the cake will release cleanly.

2. In a large mixing bowl, whisk together the all purpose flour, granulated sugar, unsweetened cocoa powder, baking powder, baking soda, fine salt, and instant espresso powder until everything is evenly combined with no visible clumps.

3. In a separate bowl or large measuring jug, whisk the buttermilk, vegetable oil, eggs, vanilla extract, and peppermint extract until the mixture is smooth, glossy, and fully combined.

4. Pour the wet ingredients into the dry ingredients and whisk gently until just combined, then slowly pour in the hot brewed coffee or hot water while whisking until the batter is smooth and fairly thin with no dry pockets remaining.

5. Pour the batter into the prepared bundt pan and smooth the top. Tap the pan lightly on the counter to remove large air bubbles, then bake for 40 to 50 minutes, or until a toothpick inserted in the center comes out with a few moist crumbs attached.

6. Place the pan on a wire rack and let the cake cool in the pan for about 15 minutes. Run a thin spatula around the edges if needed, then carefully invert the pan onto the rack or a serving plate and gently lift it away. Allow the cake to cool completely.

7. To make the peppermint ganache, place the semi sweet chocolate chips in a heatproof bowl. In a small saucepan, heat the heavy cream over medium heat until it just begins to simmer around the edges, then pour it over the chocolate. Add the unsalted butter and peppermint extract, let sit for 2 to 3 minutes, and whisk until smooth and shiny.

8. Place the cooled bundt cake on a serving platter. Slowly pour the peppermint ganache over the top of the cake, letting it drip down the sides in thick ribbons. While the ganache is still soft, sprinkle the crushed candy canes evenly over the top. Allow the ganache to set slightly before slicing and serving.