I would recommend always thawing food before putting them in the oven. Frozen food can cook unevenly leaving the middle lukewarm and the edges dry or burned. Increasing the cooking time might help, but it can also leave the food dried out. Thawed dishes will help to insure that you can time your dinner to be done when your ready. Another consideration in the extra moisture from the frost or ice that will accumulate after the dinner starts to cook. This could ruin a great dish.

It is very easy to thaw foods overnight in the refrigerator -- it just takes a few minutes of planning ahead. Depending on the temperature of your refrigerator, however, you might need to increase the thawing time (a chicken takes two days to thaw in my fridge). So keep that in mind and adjust your thawing time accordingly.

Remember, it is never a good idea to thaw any food on the kitchen counter: Bacteria may grow in the outer layers of the food before the inside thaws, leading to food poisoning. If you're short on time, you can thaw foods in the microwave, following your instruction manual. You can also thaw it in a sink of COLD water - seal it in a plastic wrapper, change the water often and disinfect the sink when you're all done. Bacteria is something you don't want to mess around with, so be sure to keep foods cool and return them to the refrigerator as soon as possible.