Beef - always use carrots, mushrooms and onions, plus a dollop of caramelised onions from a jar if I've got them in, alternatively a teadpoon of marmite. Liquid either beer, red wine or beef stock. Flour the pieces of meat before browning. Always use a bayleaf or two.
Chicken - similar but whie wine and use thyme or rosemary as well as bayleaf, maybe a bit of garlic, some cubed fried pancetta.
There's a really nce recipe for paprika chicken in the Hairy Dieters cookbook.
Alcohol and good stock cubes are what you need. Beer/red wine for beef, white wine/sherry for chicken and cider for pork. Also a dollop of creme fraiche or sour cream at the end of cooking really lifts a casserole. Oh, and dried mushrooms at the start gives it a really rich umami flavour.
Soften onions with garlic, chopped swedes and chopped carrots. Add cubed beef. Cook until browned. Add equal amounts of beef stock and ginger wine and bring to the boil. In the oven at 160 degrees for 2 hours.
Pork fillet with honey & mustard - cut fillet in half so you have two shorter lengths. Brown on all sides in a deep pan. Add half a pint of stock, turn down the heat and simmer with lid on for 20 mins. Remove meat and keep warm. Add approx 1tbsp honey, 1tbsp grain mustard, tsp sage and black pepper, increase the heat to bubble. Mix 2tsp cornflour with a little water and add to thicken. Serve medallions of pork covered in the sauce.
All amounts are approximate I'm afraid, I sort of do it by eye/taste!
I want to dump jars of sauces but have always struggled to get tasty casseroles etc. can anyone please pass on their sauce recipes for: chicken casserole, beef casserole, other chicken sauces and any for pork fillet please?