Fish pie - I buy the packs of mixed fish pieces from Asda. Co-op etc; poach in milk with a bit of black pepper, add a couple of large spoons of Philadelphia, peas and carrots, then drain and spoon into a casserole dish, cover with mashed potato and swede, top with a bit of grated cheese, pop into the oven until browned.
Cottage pie - I brown mince, finely grated onions (ds doesn't like onions so I have to hide them!), add a splash of worcester sauce, a carton of pasatta, some cooked carrots, then top with cheesy mash and brown in the oven. I always serve with baked beans :)
Tuna pasta bake - pasta, pasatta or tinned tomatoes, grated onions, tin of sweetcorn, tin of tuna, black pepper and seasoning, top with grated cheese and brown.
Casserole - slow cookers are the way forward! Any cut of meat tastes awesome in the slow cooker :) I do pork with chopped apples, chopped onions, a handful of sage and onion stuffing mix and a pint or 2 of stock.. Leave for several hours, then drain off the liquid and blend the apples and onions into it and thicken with gravy granules, or powder and cornflour. DS won't eat a lot of veg, and I find blending the way forward!
I also do cubed stewing beef, finely grated onion, mushrooms, courgette and minced beef to thicken in the slow cooker, then split into 2 portions, put a pie crust on one, and serve the other the next day with roast potatoes and roasted butternut squash and whatever veg ds will currently eat.
Homemade quick pizzas - wholemeal pitta bread, topped with pasatta, grated cheese and ham, served with butternut squash chips and ketchup to dip.
I blend lots of veg as ds can be picky, but I find grated onions, mushrooms, courgettes etc blend really easily into a tomato based sauce (use a lot of pasatta) and he will happily eat a simple meal of pasta with this sauce and a sprinkling of grated cheese.