Preheat the oven to 350 degrees F. Brush a 10-cup bundt pan with melted butter, ensuring that the inside of entire pan is coated. Dust with cocoa powder, ensuring the entire pan is covered. Tap off any excess powder and place the pan into the refrigerator.
In a large bowl, whisk together the wet ingredients - melted butter, vegetable oil, white sugar, and brown sugar. Whisk together for about 1-2 minutes, until smooth. Add in the sour cream, eggs, and vanilla extract and whisk until combined.
Add the dry ingredients - flour, cocoa powder, nutmeg, cardamom, baking powder, baking soda, and kosher salt and mix into the batter until a smooth batter forms, be careful not to overmix, mix until just combined. Pour hot coffee on top of the batter and allow it to sit for about 20 seconds, then whisk until a loose batter forms, about 10-15 seconds.
Pour cake batter into the prepared bundt pan. Bake for 45-55 minutes, until a toothpick inserted into the center of the cake comes out with just a few moist crumbs. Allow the cake to cool in the pan for 10 minutes, then turn onto a wire rack to cool completely.
While the cake is cooling, make the chocolate glaze. whisk together powdered sugar, cocoa powder, melted butter, milk, and vanilla extract. Add the tiniest a pinch of salt and whisk together. Pour on top of the cake.
Notes
Use a kitchen scale to measure the ingredients! This prevents too much flour or too much liquid being added to the batter which can affect the texture and flavor of the cake.
Be careful not to overmix your batter. After adding the flour mixture, mix until it's just combined and stop! This will ensure you get a beautiful soft crumb just like the delicious chocolate cake donuts we all love!
Use room temperature ingredients - this allows the batter to mix together more easily, creating a smooth, even texture that traps air properly during mixing. This leads to better structure, improved rise while baking.
Grease the bundt pan liberally. Use a baking spray with flour or a homemade mix of butter + cocoa powder (listed in the recipe card). Get into every nook and cranny—especially if your pan is a pretty/fun shape.
Before baking in the oven, tap the bundt pan against the counter a few times. This helps release any air bubbles, giving you a smoother, more even crumb