Stuffed Shells with Ground Beef - Real Food Whole Life

Ingredients

• 27 jumbo pasta shells
• 1 teaspoon olive oil
• 1 onion (chopped)
• ¾ teaspoon kosher salt (divided)
• 2 garlic cloves (chopped)
• 1 pound lean ground beef
• 28 ounces marinara sauce
• 1 (15-oz) container part skim ricotta cheese
• 1 egg
• 1 (16-oz) package frozen spinach (thawed and squeezed well)
• 2 cups part skim shredded Italian cheese blend (or shredded mozzarella) (divided )
• ½ cup parmesan cheese (divided)
• Chopped fresh parsley