If you have already baked the cauliflower, I would suggest double the amount of honey in the honey-tahini sauce and pour generously. The honey would cut the blazing spice to a more tolerable level. You can also add some kind of yogurt dip that will cool down the burn. If you haven’t baked the cauliflower yet, you can either add more cauliflower florets or gently rinse out the cauliflower under cool water and remake the harissa seasoning. If you are doing this, wipe the cauliflowers dry after, else they will get soggy in the oven.