Grilled Pesto Shrimp - Once Upon a Chef

Ingredients

• 2 pounds extra large (26/30) or jumbo shrimp, peeled (tails left on) and deveined, thawed if frozen
• 6 tablespoons extra virgin olive oil
• 1 cup basil leaves
• 3 large garlic cloves, roughly chopped
• ¼ teaspoon red pepper flakes
• ½ teaspoon salt
• ¼ cup grated Parmigiano-Reggiano
• ¼ cup walnuts
• 1 lemon, cut into wedges, for serving (optional)