Heat 1 cup of heavy whipping cream in a small saucepan over medium heat until it bubbles gently, then remove from heat.

Stir in 8 ounces of dark or semi-sweet chocolate chips and optionally, 1 tablespoon of light corn syrup. Let sit for 5 minutes, then whisk until smooth.

Incorporate 2 tablespoons of unsalted butter and a pinch of salt, mixing until fully combined. Allow ganache to cool to room temperature.

In another saucepan, combine 1/2 cup of water with 1/2 cup of granulated sugar on medium heat, stirring until sugar is dissolved. Bring mixture to gentle boil and whisk in 2 tablespoons of cocoa powder. Let cool.

Preheat oven to 350°F. Line muffin pan with cupcake liners.

In a large bowl, whisk together 1 ¾ cups of flour, 1 ½ cups of sugar, ¾ cup of cocoa, 1 tsp baking powder, ½ tsp baking soda, and ½ tsp salt.

In another bowl, mix 1 cup warm water, 1 cup sour cream, ½ cup oil, 1 egg, 2 tsp vanilla, and optional 1 tsp espresso. Gradually combine wet and dry ingredients until just mixed.

Fill cupcake liners about three-quarters full with batter. Bake for 20-22 minutes until a toothpick comes out with moist crumbs. Let cool for 10 minutes in pan before transferring to a wire rack.

Melt 6 ounces of dark chocolate until smooth. Beat 1 cup unsalted butter until fluffy, mix in ¾ cup cocoa, ¼ tsp salt, 2 tsp vanilla, and 4 cups powdered sugar, adding in melted chocolate. Adjust texture with heavy cream if needed.

Once cupcakes are cool, poke holes in center of each cupcake. Brush tops with simple syrup, core out a small section, and fill with ganache. Pipe frosting on top, adding chocolate shavings if desired.