Sourdough Pesto Pizza (sourdough discard recipe!)

Ingredients

• 1-1/2 cups basil leaves (washed and dried, stems removed)
• 1 to 2 cloves garlic (medium-sized)
• 1/3 cup Parmesan cheese (shredded or grated)
• 1/4 cup walnuts (or pine nuts)
• 1/4 cup extra virgin olive oil
• 1/2 to 1 cup sourdough starter
• 2-1/2 tablespoons pesto (per pizza (very flexible, adjust amount to taste))
• 1/3 cup mozzarella cheese
• desired toppings (fresh sliced tomatoes, pepperoni, basil leaves, etc.)