The time given for baking cakes is approximate. Open door carefully and just enough to test cake quickly. The cake should be well risen and evenly browned. Touch the surface lightly and, if it seems firm to the touch, the cake is done. If the impression of the finger remains the cake is not ready. Insert a warm skewer into the cake; if it comes out dry the cake is ready. If the cake is shrinking from the sides of the tin it is probably over-baked.