The best moist Chocolate Ganache Cake

Chocolate cake
0 Preheat your oven to 350°F. Grease an 8-inch springform pan, dust it lightly with cocoa powder, and line the bottom with parchment paper.
2 In a medium bowl, sift together the flour, cocoa powder, baking soda, baking powder, and salt, then set it aside. 
3 In a large bowl, whisk together the oil and sugar for about 1 minute, until well combined. Add the eggs one at a time, mixing after each one. Stir in the vanilla and sour cream until smooth.
4 Gradually add the dry ingredients and coffee, alternating between the two, mixing until everything is incorporated. 
5 Pour the batter into the prepared pan and bake for 30-40 minutes, or until a toothpick inserted in the center comes out clean. Let the cake cool in the pan for about 10 minutes, then transfer it to a wire rack to cool completely.
Ganache
7 Warm the heavy cream in a small saucepan over medium heat until it just begins to steam. (Do not boil.)
8 Place the chocolate in a heat-safe bowl and pour the hot cream over it.
9 Let it sit 2–3 minutes without stirring. 
10 Gently stir from the center outward until glossy and fully melted. Add corn syrup and mix.*If your chocolate isn’t fully melting, the cream likely wasn’t hot enough. Gently rewarm the mixture in short bursts (5–10 seconds in the microwave or over a double boiler), stirring between each round, until the ganache becomes smooth and glossy. Avoid overheating—too much heat can cause the ganache to separate.
11 Let the ganache cool until spreadable for a thicker frosting, or use it while still pourable to drizzle over the cake.