I am mixing the ground beef with dry mixes to make hamburger patties. Is it safe to refreeze these patties immediately without cooking? Ground beef is a high risk product for contamination with harmful bacteria. Freezing does not destroy these bacteria. So the risk will be even higher once you add dry mixes and shape into patties, then refreeze. The safe way to do this would be to add the mixes to the raw meat and shape into patties before the initial freezing. I purchased a 1500 watt electric oven for pizza.  There is only one control that has numbers one to five on it and no explanation as to which number should I used to cook a frozen or a fresh pizza.  Thank you! To cook the pizzas, you would normally follow the instructions written on the box where they will indicate the temperature and the time of cooking.  You will need to experiment with your oven by using an oven thermometer and see what temperatures each umber yield.   Once those values established, it will be much easier for you to use the oven. I bought frozen mix vegetables on a very hot day and had left the shopping in the car for almost an hour before I eventually got home to put my shopping away in the freezer. The frozen mixed veg packet i think was nearly thawing as i felt some of the water melting. But I still want and put the packet in my freezer as