I keep my onions in the fridge, which cuts down the tears.
+1 on mashing potatoes with the skin on. Yummy, and extra fibre too.
If you add too much liquid to mashed potatoes, add in a handful of grated cheese. It thickens it up and is tasty too. (I admit I sometimes deliberately 'oops' so I have an excuse to add the cheese...)
When making scones I melt the butter in the milk and pour in, rather than the traditional 'rub the butter into the flour'. And I don't knead the mix. The scones turn out light as a feather.
Keep a small pack of bacon and some Philly cream cheese in the freezer to add to dishes when needed. It's possible to turn a 'meh, OK' dish to 'yummo!' with the addition of one or both.