Yes you need water to create steam , it your roast can sit on the trivet that came with it. Recipes say 20 min per lb, but I do 30, add a few more minutes per in for frozen. Cook your vegetables after the roast is done, also on the trivet. Take roast out to rest after pressure has released on its own for at least 10 min.and let veg cook, pressure will come back up quickly because the pot is still hot. I don't know how long for the veg, try 8 to 12 min. Can cook potatoes in one vessel and carrots stacked on top in another ( pot in pot method) if you don't want them in the water at the bottom
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