Garlic and Spinach Stuffed Pasta Shells

Name: Garlic and Spinach Stuffed Pasta Shells
Prep time: 20 min
Cook time: 20 min
Total time: 40 min
Cuisine: British, Italian
Ingredients: 200 g (7 oz) giant pasta shells; 50 g (1/4 cup minus 1 tsp) unsalted butter; 80 g (2/3 cup) plain (all-purpose) flour; 500 ml (2 cups + 1 tbsp) milk; 130 g (1 cup + 4 tbsp) mature cheddar cheese (grated (use a vegetarian version is needed)); 75 g (2/3 cup) mozzarella cheese (grated (use a vegetarian version is needed)); ½ tsp salt; ½ tsp freshly ground black pepper; 1 tbsp olive oil; 2 fat cloves of garlic (peeled and minced); 100 g (1 packed cup) baby spinach (roughly torn); 4 tbsp panko breadcrumbs; 3 sprigs fresh parsley (finely chopped)