Preheat your oven to 325°F and grease a 10-inch Bundt pan generously.

Sift together the flour, cocoa powder, baking powder, and salt into a large bowl.

Bring butter, eggs, and milk to room temperature for easier mixing.

Cream butter and sugar on medium speed until light and fluffy (about 4–5 minutes).

Add eggs one at a time, beating well after each addition.

Reduce mixer speed and alternate adding the dry ingredients and milk, starting and ending with dry. Mix just until incorporated.

Fold in vanilla extract (and espresso powder, if using) for a flavor boost.

Pour the batter into the prepared Bundt pan, smoothing the top evenly.

Tap the pan gently on the counter to remove any air bubbles.

Bake for 55–60 minutes, or until a toothpick inserted into the center comes out clean.

Let the cake cool in the pan for 10 minutes before turning it out onto a wire rack.

Heat the heavy cream until it just starts to simmer (do not boil).

Pour the hot cream over the chopped chocolate and let it sit for 2–3 minutes.

Stir until smooth, then whisk in the butter, corn syrup, and vanilla extract.

Once the cake has cooled completely, pour the glaze evenly over the top, letting it drip naturally.