Heat oven to 400°F. Cut cauliflower heads into steaks, reserving any broken florets for another use. Place cauliflower steaks on a baking sheet lined with parchment paper. Rub cauliflower steaks on both sides with ¼ teaspoon olive oil and season with ¼ teaspoon salt for each steak. Set to roast in oven for 20 minutes, flipping halfway through.
Prepare Golden Raisins, Pistachios and Breadcrumbs
Warm white wine in a small saucier to just before boiling. Remove from heat and add raisins to plump for about 10-15 minutes.
Heat a large sauté pan over medium heat. Add panko breadcrumbs to the dry pan. Toss until breadcrumbs are toasted to a deep golden brown. Remove breadcrumbs from pan and set aside in a bowl.
In the same pan over medium heat, add 2 tablespoon olive oil. Add chopped garlic and cook until garlic is fragrant and translucent. Add chopped pistachios and stir and toss until garlic gets very lightly golden. Remove garlic and pistachio to same bowl with toasted breadcrumbs.
Drain wine from plumped raisins, then combine raisins with garlic, breadcrumbs, and pistachios. Stir in chopped parsley and 2 tablespoons lemon juice. Taste and season with additional lemon juice and salt if needed.
Assemble Cauliflower Steaks
When cauliflower steaks are finished roasting, remove them to a large serving platter or individual serving plates. Spoon the Golden Raisins, Pistachios, and Breadcrumbs mixture over. Squeeze more lemon juice over the entire dish.