You can make yourself lunches every so often. Nanako will tell you that she went grocery shopping and that the fridge is full. Inspect the fridge to make your lunch. Making lunches will take up your afterschool/evenings. Here is a list with the correct cooking answers:
Broiled Fish - Wrap it tightly
California Rolls - Mix and cool simultaneosly
Carrot & Burdock Root Kinpira - Add soy sauce and mirin
Chackin Sushi - Thinned eggs
Cream Stew - Dump in all the cold milk
Croquettes - High
Daigaku-Imo - Deep fry them
Fried Chicken - Potato starch
Ginger Pork - Score it with a knife
Grilled Fish - Strong heat but from far away
Gyoza - Olive Oil
Hamburger - Cut a hole and look for juice
Kakuni - Mirin, sugar & sake
Marinated Spinach - Strain it
Meat Stew: Simmer with a dropped lid
Mentaiko Pasta - Mayonnaise
Oden - Keep on a low flame and don't broil
Potato Salad - Smash while still hot
Pudding - Vanilla extract
Sweet & Sour Pork - Potato starch
Tonkatsu - Flour, egg then panko
Vichyssoise - Add lots of milk
Yakiniku Bento - Use soy sauce