In a blender (or food processor) add 1 cup of cauliflower florets at a time (working in batches) and pulse each batch quickly about 3-5 times or until the cauliflower is the same consistency of rice. Transfer to a large bowl and repeat with remaining cauliflower until all done.
Heat a large skillet or nonstick pan over medium heat. Add olive oil, onions, scallions (shallots) and garlic and sauté for about 3 minutes on low-medium heat, until soft and fragrant.
Add the cauliflower "rice": season with salt and pepper to your tastes; increase stove temperature to high heat. Add the lime juice and cilantro; stir mixture and cook, while stirring frequently for about 6 minutes, or until the cauliflower is tender-crisp (soft on the inside; crispy on the outside).
Serve!
Notes
If you don't mind the extra carbs, cauliflower rice can be switched out for regular rice.