As I mentioned, store-bought flatbreads have come a long way and make the perfect base for any pizza. If you have time to make your own, you can use this delicious naan recipe here. Pretty much any flatbread will work here but try and find one that is thick enough to hold the toppings. For a store-bought option in Canada, I’m a huge fan of Manoucher Bread but if that is not available to you, just seek out any flatbread at the grocery store that looks good to you. I also like to use this naan, though it's not as sturdy so you can't load it with too many toppings. A sore-bought, or homemade baked pizza crust will also work perfectly here. If using un-baked, unless you have a pizza oven, make sure to par-bake it or the toppings could burn. The shape of your flatbread won't matter but whichever one you go with, make sure it is unflavoured, or only flavoured with mild herbs. For example, the manoucher brand I mentioned sells a delicious flatbread with tarragon but it would overwhelm all the other flavours of this Brussels sprouts pizza.