What can I use instead of mushrooms?

[ILoveMakeUp]

I really want to cook this nut roast pie, but DH does not eat mushrooms. Any idea what I can use instead?

Thanks.

Aubergine might work, but you'd have to cook it for a bit longer than the mushrooms.

Beans of some sort? Lentils?

My DS detests mushrooms, I often use red peppers from a jar instead. Different, but they seem to work

actual chestnuts

will be a slightly different texture but yummy with the flavourings in that recipe.

Failing that I would say courgette/ aubergine.

Celery?

Some good ideas, thanks very much!