Can I Make Chocolate Guinness Cake Rectangular Instead Of Round?

Our answer

NIgella's Chocolate Guinness Cake (from FEAST) is a moist chocolate cake that is mixed in just one saucepan. The cake is usually baked in a 23cm/9-inch springform pan.

Unfortunately we don't have the size of the roasting pan, however we suspect that they are deeper than most sheet pans. Roasting pans would have a depth of 4-5cm/1.5-2 inches vs a sheet pan of around 2.5cm/1 inch. We would prefer to use the deeper pan. If you use a very shallow pan then the cake will be very thin and will be drier in texture. If you are using a pan that is 28x18cm/7x11 inches then you should only need a single quantity of the batter. The baking time should be around 30 minutes. If you are using a larger pan of around 33x23cm/13x9 inches then you would need to use 1.5 times the recipe quantity and the baking time is likely to be around 35 minutes. However, keep an eye on the cakes and be prepared to check them a couple of minutes before and also they may need slightly longer to cook. The cakes should be risen, firm to the touch and a cake tester insterted into the centre should come out clean or with a few damp crumbs attached. When moving cakes around there is always a risk of cracking. However, make sure that you line the roasting pan with baking parchment (parchment paper), with the paper coming up the sides of the pan. Let the cake cool completely in the pan then carefully use the paper to slide the cake onto a cooling rack or cutting board. If you can then invert the cake onto a serving platter and peel the parchment away (so the flat bottom of the cake then becomes the top of the cake) then the risk of cracking will reduce slightly, but you can always hide any cracks with frosting. Please note that as we have not tried the cake in rectangular form, we are unable to guarantee the results.