What temperature should food be when cooked?

You can bake something in a "slow oven" at 250 degrees Fahrenheit. Pizza is baked in a commercial oven at 750 degrees F. Most cooking in a home oven is in the range from 325 to 475 degrees F. Water boils at 212 degrees F. The heat output of a typical stovetop burner is 9500 BTU. So the answer is: it varies.