Easy & Rustic pesto recipe with walnuts

Ingredients

• 2 cups (packed) fresh basil leaves (about 60 g)
• 1/2 cup walnuts, toasted and cooled (60 g)
• 1/2 cup freshly grated Parmesan cheese (50 g)
• 2 cloves garlic, peeled (about 8 g)
• 1/2 cup extra virgin olive oil (120 ml)
• 1 tablespoon fresh lemon juice (optional, about 15 ml)
• Salt, to taste (start with 1/2 teaspoon sea salt)
• Freshly ground black pepper, to taste