Step 1

Preheat the oven to 350°F (180°C). Butter and line with parchment a 9-inch (23cm) springform pan. Set aside.

Step 2

In a large bowl whisk together the melted butter, cocoa powder, granulated sugar, brown sugar and the Guinness.

Step 3

Whisk in the sour cream, and then the eggs and vanilla extract until fully combined.

Step 4

In a separate bowl, combine the flour, baking soda, and salt. Whisk the flour mixture into the chocolate mixture until evenly mixed.

Step 5

Pour the batter into the prepared pan and bake for 45-60 minutes, until a skewer inserted in the middle comes out clean. Let the cake cool completely in the pan.

Step 6

While the cake is cooling, prepare the butter glaze: combine the butter, chocolate, and honey in a microwave-safe bowl or in a small saucepan and heat gently until the butter and chocolate melt. Stir together and let cool until thickened but still pourable.

Step 7

Once the cake has cooled, transfer the cake to a serving plate and pour the glaze on the cake. Let the glaze set for an hour or two before serving if you wish.

Step 8

Store any leftover cake in an airtight container at room temperature for up to 3 days. For longer storage, freeze in an airtight container for up to 2 months.