Vegetarian French Dips

I made Portabella Mushroom French Dips last night.  They turned out good!  It probably wasn't totally vegetarian, because I used Lipton's french onion soup mix, but close enough for me.  I also added a piece of provolone cheese and I didn't put in the liquid aminos (what are those anyway???)  I used a whole wheat french bread, and we would have liked a different bread -- something sourdough, maybe?  It makes a lot of au jus, so I really don't think the seven cups of water are necessary!  If I cut down on the water, I would also cut down on the vinegar and use only one package of onion soup mix.  I put the rest of the juice in the fridge, so I can use it for vegetable stock (and we are going to put some of it on Mollie's food for a treat.)