Christmas cake

Oh no, sorry, I didn't explain myself well enough - it was already in the oven!!! I switched the oven off at 3 1/4 hours and left the cake in, and it looks OK, so fingers crossed! Thank you for the replies tho, very kind

Agree with Monica better to bake it another day ( and if that day never dawns, buy one from M&S)

Does it matter when you make the cake? Why not just make it at a more convenient time.

I do not think switching the heat off and turning it back on some hours later would be a good idea. The cake will sink as the mixture, which will not be full cooked will sag and reheating will not get it rising again.

If the recipe has raising agent in it either as SR flour or as baking powder the raising agent reacts with the liquid in the cake to produce carbon dioxide bubbles in the mix which makes it rise and the cooking 'fixes' the bubbles so that they stay in the finished cake. If you cook the cake in two parts by the time you put it back into the oven the chemical reaction will have ended and the cake deflated and will not reinflate when you start cooking again.