T - DODAR
As has been stated above T-DODAR is the method currently preferred by BA for managing in flight emergencies.
The breakdown of the elements given by 757 Driver is correct, the only mild amendment I would suggest is the A.
Normally it is not just to "action" but to "assign" tasks with the expectation they will be actioned. This therefore allows the P1 to manage the situation by assigning tasks to not only his/her P2, but also the whole crew, including ATC! It's almost the same but slightly broader brush.
As has been mentioned the most critical part of the process is the review and assessing whether the initial decision was in fact the correct one. If it appears not to be...back to the start and T-DODAR again. It may seem cumbersome but it does work, both in the sim and in practice.
Hope it helps, and good luck to those in the process.