Pistachio-Parsley Pesto and Grilled Taleggio Cheese Sandwich

INGREDIENTS

• Pesto:
• 2 tablespoons shelled, roasted pistachios
• 1 clove garlic
• 1½ cups packed parsley
• 2 tablespoons lemon juice
• 2 tablespoons olive oil
• ¼ teaspoon salt.
• ½ small red onion, thinly sliced
• 3-4 ounces taleggio cheese, sliced
• 4 slices whole wheat or multigrain bread
• Olive oil for brushing