Ravioli with Pistachio Pesto - Serving Dumplings

Ingredients

• 3 ounces pistachios
• 1 ounce grated pecorino
• 2 tbsp lemon juice
• ¼ tsp salt
• 1 tsp black pepper (more for serving)
• ¼ cup basil leaves
• 6 tbsp olive oil (divided)
• 1 tbsp unsalted butter
• 2 garlic cloves (minced)
• 1.3 pounds ravioli (with your favorite filling)
• crushed red pepper flakes (for serving)