Cauliflower steaks:
1 head of each of Frieda's purple, orange and green cauliflower
3 tablespoons plus 1 teaspoon olive oil
1/2 teaspoon garlic powder
1 teaspoon salt
1/2 teaspoon black pepper
2 teaspoons paprika
Fresh parsley, chopped
Romesco sauce:
2 red bell peppers, sliced in half lengthwise and seeded
2 teaspoons plus 1 tablespoon olive oil
1 cup fresh parsley
1/2 cup raw almonds
1/4 teaspoon smoked paprika
1 tablespoon red wine vinegar
3/4 teaspoon salt
For the cauliflower steaks, preheat grill to high heat.
Trim stems and outer leaves from cauliflower, but keep big center stems intact. Carefully slice cauliflower down middle, then slice again to create 1-inch slabs. Reserve any florets that fall off in large bowl.
Combine garlic powder, salt, pepper and paprika in small bowl. Brush both sides of steaks with olive oil, sprinkle with seasonings (reserve a bit for florets), then grill 5 minutes on each side, or until slightly charred and tender.
Toss loose cauliflower florets with a teaspoon of olive oil and remaining spices. Wrap in foil packet and grill alongside cauliflower steaks.
Transfer grilled steaks to serving board; place florets in serving bowl. Garnish both with chopped parsley and serve warm.
For the Romesco sauce, preheat oven to 400 degrees.
Line baking sheet with parchment paper. Place red bell peppers cut side down on paper, then brush with 2 teaspoons olive oil. Bake 35-40 minutes, until skin is blistered. Set aside to cool.
When cool enough to handle, peel skin off peppers and discard. In food processor bowl, add peppers, tomatoes, parsley, almonds, paprika, vinegar, salt and 1 tablespoon olive oil. Process until creamy and smooth, scraping down sides as needed.
Transfer romesco sauce to bowl and serve with grilled cauliflower steaks.