Preheat oven to 200°C. Sprinkle the steaks with fennel seeds then season with salt and pepper. Drizzle with half the avocado oil and set aside. Toss the cauliflower, eschalots and half the garlic with the remaining avocado oil, season with salt and pepper, then arrange in a roasting pan and bake for 45 minutes, until golden.
Combine the basil, pine nuts and remaining garlic in a mortar, then pound until a coarse paste forms. Mix in the Parmesan and olive oil then season with salt and pepper.
Cook the steaks on a hot barbecue grill for 10 minutes, turning regularly, until medium. Rest for 2 minutes, then serve with the cauliflower salad and pesto.