Pre-heat oven to 200°C / 400°F.

Slice bell peppers and onion.

In a small bowl, whisk together the olive oil, lime juice, cumin, smoked paprika, garlic powder, salt and pepper.

Transfer the sliced bell peppers and onion to an appropriately sized baking dish. Add half of the olive oil mixture, and toss to combine. Place in the oven and let roast for 15 minutes.

Meanwhile, add shrimps to the bowl with the remaining olive oil mixture. Toss to combine. Cover and let marinate in the fridge.

Wash and thoroughly dry cauliflower. Remove all the leaves. Cut into large chunks. Then, using a box grater, grate cauliflower into "rice.

After 15 minutes, remove baking dish from the oven and give the bell peppers and onion a toss, then push them to one side of the baking dish. Add cauliflower rice to the other end. Return to the oven and let roast for 5 minutes.

After 5 minutes, remove baking dish from the oven and place marinated shrimps on top of the cauliflower rice. Arrange them in a single layer to ensure even cooking. Return baking dish to oven and bake for 10 more minutes or until the shrimps are cooked through (pink and no longer opaque).

Remove baking dish from the oven, and season cauliflower rice with salt and pepper to taste.

To serve, divide cauliflower rice among 4 serving bowls. Top with shrimps, bell peppers, onion and guacamole. Serve with lemon wedges. Enjoy!