Since dogs tend to scoff their food - well Gus does anyway, I've stayed clear or peas & corn. They don't seem to digest at all - comes out whole - the corn can obstruct their intestinal tract. Especially if it's the cob - Absolute no.no.
I cut up the stalks from broccoli, carrots, potatoes, whatever is available. A few minutes with a bit of water, in the microwave to soften them. And a Hi-Fibre Weetbix - as advised by my vet. All this with fresh meat & dry dog food- we love to spoil them don't we. :D