Best food stuffing toy???

I've currently got a large or medium kong. Axel does love it and it's working a little more to distract him as we go out. But if for some reason he's stressed when we leave, he won't touch it.
He's now having to be back downstairs when we go out because of his leg not being 100% better, so we felt it better for him only going upstairs once a day so his leg gets stairs rest.
Anyway, so because of this, I'm on the hunt for food stuffing toys that are perhaps more irresistable and will help distract him from being in the den now....any favourites for your dogs????

Stressed dogs often won't eat and I imagine you'll probably have to deal with the stress more than the kind of dispensor. Kongs are probably one of the most open kind of toys, e.g. as opposed to treat balls which are more contained, so the Kong makes it more obvious there's food on offer.
You could maybe try making the Kong a little easier to empty, don't stuff it so tightly (and maybe leave two so he gets the same amount of food as a tightly packed one), or you could even just scatter food around the room so he just has to find tit, but I think you'll have more success by going back to basics and slowly getting him used to being left in the den by himself, so he stresses less when left.

Thanks for the reply. Yes, he won't eat when stressed. He took a long time to accept food out on walks even. It's hard because he was getting much better generally being left upstairs and was eating his kong, but I have to consider his leg. For some reason the den has become a stressful place but it's our only choice. So I was hoping to use the kong in conjunction with doing lots of practice leaving. We've started feeding him in there to try and build positive experiences there. I hoped food would help over time.

We've got a kong, a kong wobbler which I put his kibble in, and some kind of purple dumbell which squeaks if you shake it at the right angle and that you can put a few treats in either end of (just enough to give it that very random incentive if one will come out or not). We mix up which ones we leave out - but he loves the wobbler and the purple dumbell thing (which we put out less often than the other two to keep the novelty value high).

We've been known to walk out of the back door and then peek back through the kitchen window and you have a milisecond of "oh, you've gone" followed by an "ok dinner get out of that wobbly thing and into my mouth" frenzy