Beth:

I don't claim this is the exact thing I do every time, but this
is what I did Sunday.

3 cloves garlic, finely minced
1/2 teaspoon lemon zest
Juice of 1 lemon
2 teaspoons dried oregano
1 teaspoon salt
1/2 teaspoon ground pepper
3 tablespoons olive oil

Trim the bottom leaves and stem of one head of cauliflower so
that it sits flat.  Mix up the ingredients above and spread all
over the outside of the cauliflower.  A paintbrush makes this
easier.  Put in a shallow pan and roast in a 350 degree oven
for 1 1/2 hours.  Baste once or twice with the drippings.  If
the drippings start to smoke you can add a little broth or
water and baste with that.

Enjoy.