Preheat the oven to 450°F and position the oven rack in the center.
Rinse the 1 medium cauliflower, remove outer leaves and the core, and break into small "popcorn"-size florets (bite-sized pieces).
In a small bowl, mix the spices: 1 teaspoon salt, 1/4 teaspoon onion powder, 1/4 teaspoon garlic powder, 1/2 teaspoon paprika, and 1/2 teaspoon ground turmeric.
Place the cauliflower florets in a zip-top (resealable) bag. Add 1 tablespoon olive oil and the spice mixture to the bag, seal, and shake/toss until the cauliflower is evenly coated.
Spread the coated florets in a single layer on a baking sheet (do not overcrowd).
Roast uncovered in the preheated 450°F oven for 25–30 minutes, turning or shaking the baking sheet once halfway through, until florets are tender and edges are golden.
Remove from the oven and let cool briefly before serving.