I do trench composting and layering as a part of my garden work
it works quite well! I had a sterile yard 4 years ago and now I have TONS of worms!! they do great things for the garden!
my suggestion is layers. layer the newest material, more composted material, paper products (to keep volunteers down) grass clippings, good soil, leafs and mulch.
that layering system allows me to get heat going and the composting processes maintain through my winter for awhile and keep the worms happy for longer.
the larger the layer of the top three the better it will smell.