Cheesy strata with bagels, dried sausage and spinach

Ingredients

• 2 cups milk
• 10 big bio eggs
• 1/2 teaspoon dried parsley
• 1/2 teaspoon paprika
• 5 whole wheat bagels, split in half then cut in 8
• Olive oil
• 150g craft dried sausage, cut in mini cubes
• 8 white mushrooms, sliced
• 1 yellow onion, finely chopped
• 4 cups compact baby spinach
• 1 pint (551ml) raisin tomatoes, cut in half
• A handful fresh parsley, chopped
• 20 fresh basil leaves, chopped
• 2 cups sharp cheddar grated
• One 226g ball of fresh mozzarella
• Salt and ground pepper