Preheat the oven to 425° F. On a baking sheet, toss together the olive oil, cauliflower, paprika, chili flakes, fennel seeds, mustard seeds, onion powder, garlic powder, and salt. Add the shallots. Toss well to evenly coat. Transfer to the oven and roast for 15-20 minutes, or until tender.Rub a large baking sheet with olive oil. Increase the oven temp to 450° F.On a lightly floured surface, push the dough out until it's pretty thin (about a 10-12 inch circle). Transfer the dough to the prepared baking sheet. Spread on the marinara sauce, add the cheeses, then arrange the shallots and cauliflower "pepperoni" over the cheese.Bake for 10-15 minutes or until the crust is golden and the cauliflower is crisp. Remove from the oven and top with fresh basil. Slice and enjoy!