Never done it, and have been advised not to try as it could take a long time to find an empty bowser. The fuel company would be the only ones with a bowser. In my day, 'defuelled' fuel could not be re-used in an aircraft. I do not know how long it would take to organise. The 'quickest' option is to reduce payload if it is a take-off weight problem. To burn-off 10T en route to Geneva if was a landing weight problem would be extremely difficult! To tie to the thread, it would be very difficult to remove only the baggage of the 37 off-loads from the aircraft.
Other option (if ldg weight limited) which may or may not be possible depending on programme would be to swap a/c onto another, longer route, but still difficult to get rid of 10T! T'was a screw up.
Fuel may have been loaded before flight crew arrived at the a/c, in their defence. I have caught an over-enthusiastic bowser 3 times in my career but luckily in time to avoid performance problems.