Juicy Burgers with Chunks of Basil Pesto Butter - Sutter Home Family Vineyards

Ingredients

• 1/4 cup pine nuts
• 2 cups of basil (packed) leaves
• 2 garlic cloves (minced)
• 1/2 cup grated parmesan cheese
• 2 tablespoons of lemon zest
• 1/4 cup olive oil
• 2 sticks of Salted butter (room temperature)
• 1 3/4 ground beef (15% fat)
• 6 hamburger buns, split horizontally
• 1 1/2 tsp coarse salt
• ½ tsp freshly ground Pepper
• 6 slices (1/4 inch slices) fresh Buffalo mozzarella cheese (about 8 -10 ounces)
• 5 oz baby romaine leaves
• 1 cup cherry tomatoes (halved)