INCREDIBLY DELICIOUS dinner! Juicy, tender casserole with tuna and rice

Ingredients
🔹 1 cup rice
🔹 2 glasses of water
🔹Teaspoon salt
🔹 Olive oil
🔹 1 onion
🔹 2 cans of tuna in oil
🔹 A few sprigs of parsley
🔹 Butter
🔹 3 eggs
🔹 100 ml (3.5 fl oz) milk
🔹 Pinch of salt
🔹 150 g (5.3 oz) cherry tomatoes
🔹 Italian herbs
🔹 70 g (2.5 oz) mozzarella