Adapters exist for providing 120V from a 240V receptacle, such as for powering a gas range or dryer from the original electric range or dryer outlet:

Does anyone make a similar adapter that goes in the other direction?
Specifically it would plug into an existing 120V split kitchen receptacle and provide a 240V outlet for a European kitchen appliance? (It would be for resistance appliances only, so the 50Hz vs. 60Hz is not an issue.)

It would be easy to construct one, but the result would be potentially dangerous.
(Two separate 120V plugs means that when one is plugged in the other has a live exposed prong.)

What would be needed is a dual plug, such as this wall-tap has, but with only a single 240V outlet:

Adapters exist for providing 120V from a 240V receptacle, such as for powering a gas range or dryer from the original electric range or dryer outlet:

Does anyone make a similar adapter that goes in the other direction?
Specifically it would plug into an existing 120V split kitchen receptacle and provide a 240V outlet for a European kitchen appliance. (It would be for resistance appliances only, so the 50Hz vs. 60Hz is not an issue.)

It would be easy to construct one, but the result would be potentially dangerous.
(Two separate 120V plugs means that when one is plugged in the other has a live exposed prong.)

What would be needed is a dual plug, such as this wall-tap has, but with only a single 240V outlet: