Get a slow cooker and a steamer. Sometimes Argos have 3 dor 2, if they do then get a rice cooker too.
You can cook whole joints / whole chicken in a SC.
In a steamer you can put meat or fish wrapped in foil with a selection of veg.
With a SC and a steamer plus your microwave you can do a full Sunday dinner.
Meat in the SC, veg in the steamer, roast potatoes and Yorkshires in the combi.
15 mins before you eat take the meat out, wrap in foil and make gravy in the SC.
Pasta with lemon - cook some spaghetti, grate the peel of a lemon and squeeze the juice out of it.
Once the pasta is cooked add the lemon juice, zest and black pepper.
Do you have a toaster? Baked beans cook quickly in a microwave and there is less washing up.
You can also do baked potatoes in a slow cooker.
The usual SC things like stews, soup, chili are easy.
I also use my SC to steam suet puddings, line a pyrex dish with suet pastry, add floured meat (steak and kidney with onion is traditional but check and leek can work).
Cruble in a stock cube then make a pastry lid, put that on and make a hole in the centre.
Boil the kettle.
Fold up a tea towel and put the pyrex dish with pudding on top. pour boiling water in to the hole until it it spills, pour the rest of the boiling water into the SC to come about half way up the side of the dish.
If you want to you can put veg in the water to cook but I generally find a pan is less fuss.