Preheat a convection oven to 350ºF and line a large rimmed baking sheet with parchment paper or silicone baking mat.
Using a sharp knife, trim the leaves off of the cauliflower and cut the end stem (leaving enough to keep the cauliflower intact). Cut the cauliflower in half down the middle.
Take each half of the cauliflower and cut them into 1-inch slices. With 1 cauliflower, we ended up with 3-4 steaks and some florets leftover that you can bread and bake as well or set them aside for another use.
In a large wide bowl, whisk together the vegan yogurt and milk. Set aside.
In another wide bowl, mix together the panko breadcrumbs along with all of the remaining ingredients except for the cornstarch. Set aside.
Pour the cornstarch onto a large wide plate.
Dunk the cauliflower steaks into the cornstarch, dip them into the yogurt mixture, and then press them into the panko mixture, being sure it is fully coated on all sides. If necessary, use your hands or a spoon to sprinkle over the breadcrumb mix.
Bake the steaks for 15 minutes, carefully flip them over, then place back into the oven bake for another 8-10 minutes, or until golden brown and crispy. Allow them to cool before serving.
The nutrition facts for this recipe to not include the gravy.