Preheat the oven to 425F. Add parchment paper to an extra large baking sheet or to two regular baking sheets.
Cut the cauliflower florets from the stem. Cut cauliflower florets down into similar size, bite sized pieces so they can cook evenly.
Chop the sweet potatoes into ½ -1 inch cubes (try to make them all similar sizes).
Add the veggies to the baking sheet (or divide them between the two smaller baking sheets). Drizzle them with olive oil.
Combine the spices in a small bowl. Sprinkle spices over veggies.
Using clean hands or tongs, toss the veggies in the olive oil and spices, ensuring all the spices are off the the bottom of the pan and on the veggies and all the veggies are well coated).
Arrange the vegetables in a single layer, ensuring no piles of veggies exist. This helps them cook evenly and not steam.
Roast at 425F for 35-45 minutes. Check around 30 minutes and stir if needed.
