Preheat the oven to 400 degrees F (200 C). Line a baking tray with parchment paper, and cut the cauliflower into florets.
Into a large mixing bowl, add the flour, garlic powder, salt, and mix everything.
Add the milk and stir until combined. The mixture should be thick.
Add the cauliflower florets and coat them evenly.
Into a separate bowl, add the panko bread crumbs. Transfer the cauliflower florets to that bowl and coat them with the bread crumbs.
Place the coated florets into the baking tray without touching each other and bake for about 20 minutes, flipping over halfway through.
While the florets are baking, mix the barbecue sauce with paprika, and melted butter, set it aside, prepare the vegetables and make the dressing.
To make the dressing, add all dressing ingredients into a measuring cup and blend with an immersion blender until you achieve a creamy consistency.
Remove the florets from the oven, brush each one with the barbecue sauce mixture and return to the oven to cook for additional 20 minutes.
To assemble the tacos, take a tortilla, add the shredded cabbage, avocado, and cauliflower bites on top. Garnish with coriander, lime juice, and garlic dressing on top.