Steamed Sole Roulades with Wilted Greens

Ingredients

• ¼ cup extra-virgin olive oil
• 2 tablespoons white wine vinegar
• ½ teaspoon sea salt, divided
• ¼ teaspoon freshly ground black pepper, divided
• 1 roasted red bell pepper, cut in 1/4-inch strips (bottled is fine)
• 1/2 red onion, thinly sliced
• 1 clove garlic, chopped
• 6 cups (about 3 ounces) mixed greens
• 1/2 teaspoon unsalted butter
• 1 tablespoon chopped shallots
• 3/4 pound sole fillets
• 1 tablespoon chopped fresh tarragon (or 1 teaspoon dried)
• 1 tablespoon dry white wine