Preheat oven to 400F and lightly grease a large sheet pan.
Toss cauliflower, carrots, onion, vegetable oil, garlic, ginger, and spices together on sheet pan until evenly coated. Season with salt and pepper to taste and arrange in a single layer on sheet pan.
Roast vegetables at 400F 25-30 minutes until golden brown and tender.
Place vegetables and broth in a blender. Blend on high speed until completely smooth.
Pour blended soup into a medium pot. Bring to a simmer over medium-high heat, reduce heat to low, and allow to simmer 8-10 minutes, stirring occasionally. Add a few splashes of additional broth if needed to thin soup after simmering.
Season soup with salt and pepper to taste and serve warm with cilantro and paprika sprinkled on top. Enjoy!