Breakfast and lunch are cold meals in our house (actually it's a boat not a house at the moment) but I cook one-pot meals for 2 or 3 days or more and freeze some. My latest favourite is Mixed Veg Goulash. The ingredients are:
2 Tbsp olive oil, 1 large red onion, 1.5 Tbsp smoked paprika, 400g can chopped tomatoes, garlic, 400g can mixed beans, rinsed, 1 oxo stock cube (or other brand),
1 tsp oregano, 3 small peppers, sliced, salt and pepper. Fry the onion, garlic and spices, 3 minutes, add the rest (except beans and cook for 15 mins, adding water if it's dry. Add the beans last and heat through. I prefer red kidney beans but any beans are fine. This is for 2 people. Only one pot to clean and if you double the quantities (or treble) you can have 2 or 3 days off cooking