I bought a Mary Berry Christmas cake mix from tesco earlier in the week when it was cooked according to the instructions it cake out burnt... Yuck. So as my son wanted this cake for his grandad we went and bought another mix started all over again and same thing burnt.... Bloody hell. I have tested my oven and even cooked another mary Berry cake mix and no problems. This mix is not cheap and each mix cost me £10 !! I know madness plus a pack of butter and 4 eggs each time. So am I being unreasonable to expect a refund ????