Low Carb Broccoli Soup

INGREDIENTS

• 1 tablespoon extra-virgin olive oil
• 1 large onion, finely chopped
• 2 cloves garlic, minced
• 2 pounds broccoli, chopped
• 1/4 teaspoon salt
• 1/8 teaspoon ground black pepper
• 5 cups vegetable broth
• 1/4 cup freshly squeezed lemon juice
• 1/4 cup shredded Cheddar cheese, or as desired (optional)