MSG. My favorite use for it is in soups. It only takes a small amount and it makes a significant difference.
Slow cookers are awesome for preparing dry beans, infused oil, and roasting beets in aluminum foil.
Know your emulsifiers and keep them handy. I always have a nice mustard as well as soy lecithin on hand, and if I’m ever worried about an emulsion breaking or I want a nice even sauce or dressing, I have at least one neutral and one savory option. Soymilk also works if it works for your recipe.