Oh blimey some really rubbish advice from some behaviourists.
Do not ever follow this advice "We had the behavioural people from the blue cross come round and to get her to like my husband he'd offer her chicken and pick her up and hug and love her" Please never ever do this, you have a frightened anxious dog that is conflicted as they want the food but the giver of the food is causing them stress, this situation is an accident waiting to happen.
or
trying to give a dog food when they will not eat - over threshold in the poodle . example. A qualified behaviourist would be able to work out was is rewarding for each dog individually for some it may literally be turning away from the dog as they see it, for others it may be watching the dog from a distance, food may be used but food is not the only reinforcer for many dogs.
You cannot "train" a dog to not be reactive. You need to change the emotional response to a trigger. This takes time. Aversive training or being firm with the dog will not change the emotion but may suppress the behaviour. eg the dog may not bark and lunge as they know something unpleasant will happen. What tends to happen is the dogs holds in the emotion and then will literally get to threshold and the response will be mega. The fear emotion has been increased.
It is not a matter of just giving food when the dog is in the worrying situation.
The dog needs to recognise the food appears because of the situation.
So dont distract your dog with food, dont give the dog food when you see the trigger it must be when the dog has, dont give the food when the trigger has gone or else you are just giving food!
OP what is your dog barking and lunging at?
I do understand that the quick fix of these online trainers is tempting but it does not work long term. In my line of work I have a lot of these owners coming to me to sort out the long term issues caused by this type of training.