A big pile of food will take forever to cook and may never turn brown and caramelize, so when you're roasting food, it's important that you don't crowd your pan.  Spread your food into an even layer; each piece should...

When shopping for citrus fruits like oranges (or lemons, limes, grapefruits, clementines, etc.), you want to choose fruits that you can imagine being able to squeeze easily for juice.  Hold them gently in your hand to get a feel for how hard or soft they are...

Here's an easy trick to tell if fish is fully cooked - press on the fish with the back of a spoon. If the fish flakes apart (or cracks) easily, it's cooked. If the fish still seems quite firm, as if it's pushing back at you rather than falling apart, then cook it a bit longer.

To check how ripe an avocado is, hold the avocado gently in your hand to get a feel for how soft it is.  A ripe, ready to eat avocado will feel somewhat soft, but not mushy - firm, but with a bit of give.  It may have black or greenish skin.  Avoid avocados that feel like they have air pockets inside...

Oven mitts are meant to protect your hands from hot pots and pans, but if you're not careful, they can do just the opposite.  If your oven mitt (or kitchen towel, or whatever you use to hold hot things) has holes in it, don't use it - you will get burned. And don't even think about using a wet oven mitt...

Once potatoes are cut up, their white flesh will start to turn brown. To prevent this from happening, simply store your chopped potatoes in a container of water.  (Be sure the water covers all the potato pieces.)  When you're ready to cook, drain the potatoes and pat them dry, and you'll be ready to go!