We’re really happy with this thermometer from Thermoworks, which has sufficient range for general cooking (eg, roast pork), and candy-making. Temperature-readout is very accurate and wicked-fast (you don’t want to be hanging around waiting for a temperature when you’re boiling caramel) and the version we have is splashproof. Yes, it’s expensive at around $90, but definitely worth it when you need to trust your cooking thermometer.
We use this in (among other recipes):
Pretty much any recipe where you read “…a greased baking sheet…” you can replace it with “a Silpat”. This is a silicone surface which helps to even out the temperature of the baking surface and prevents a baked good from sticking. Take care of them and they’ll last for years.
We use these in: