Flourless Chocolate Ganache Cake

Ingredients

• 1 cup semisweet or bittersweet chocolate chips (like guittard)
• 1/2 cup (8 tablespoons) unsalted butter
• 3/4 cup granulated sugar
• 1/4 teaspoon salt
• 1 to 2 teaspoons espresso powder, optional (1 teaspoon will enhance the chocolate flavor and 2 teaspoons will give you a mocha flavor)
• 1 teaspoon vanilla extract
• 3 large eggs
• 1/2 cup unsweetened cocoa powder (like ghiardelli)
• 1 cup semisweet or bittersweet chocolate chips
• 1/2 cup heavy cream
• 1/3 cup packed brown sugar
• 3 tablespoons butter
• 1 tablespoon milk
• fresh whipped cream, for serving, optional