Oven smoke often comes from grease or spilled food burning on hot surfaces, but it can also indicate unsuitable cookware, excessive temperature, or an electrical fault. If smoke is heavy or smells electrical or plastic-like, turn the oven off and stop cooking.
Check whether the smoke followed a spill
Cheese, grease, sugar, and sauces on the oven floor or pans can smoke as they heat. Let the oven cool completely and clean the residue according to the manual before the next use.
Check oil, paper, and cookware
Oil above its smoke point, parchment too close to a heating element, or unsuitable cookware can create smoke. Correct the cause and follow the material’s temperature limits.
A new oven may require a first-use burn-in
Some manufacturers specify an initial burn-in cycle to remove production residues with proper ventilation. Follow that manual procedure exactly; do not assume persistent smoke from an older oven is normal for the same reason.
Electrical smoke, arcing, or flame is a stop condition
Turn the oven off and disconnect power from a safe control if that can be done without approaching danger. If there is a fire, leave and call emergency services; do not repeatedly open the door to inspect it.