16 jumbo pasta shells (Cook a couple of extra shells to allow for a few breaking while the pasta cooks.)
1-1/2 tbsp olive oil
2 tsp fresh garlic, minced
4 cups (packed) fresh spinach leaves, roughly-chopped
12 oz skim-milk ricotta cheese
1 cup shredded skim-milk mozzarella cheese
1/2 cup grated Parmesan cheese, plus more for serving
1 large egg
1 tbsp fresh basil, finely chopped
1 tsp kosher salt
1/2 tsp freshly-ground black pepper
1-1/4 cups marinara sauce