Duck soup
(USA) If something is duck soup, it is very easy.
Easy as pie
If something is easy as pie, it is very easy indeed.
Easy peasy
(UK) If something is easy peasy, it is very easy indeed. ('Easy peasy, lemon squeezy' is also used.)
Eat humble pie
If someone apologises and shows a lot of contrition for something they have done, they eat humble pie.
Eat someone alive
If you eat someone alive, you defeat or beat them comprehensively.
Egg on your face
If someone has egg on their face, they are made to look foolish or embarrassed.
Fall off the turnip truck
(USA) If someone has just fallen off the turnip truck, they are uninformed, naive and gullible. (Often used in the negative)
Fine words butter no parsnips
This idiom means that it's easy to talk, but talk is not action.
Finger in the pie
If you have a finger in the pie, you have an interest in something.
Food for thought
If something is food for thought, it is worth thinking about or considering seriously.
Forbidden fruit
Something enjoyable that is illegal or immoral is forbidden fruit.
From soup to nuts
If you do something from soup to nuts, you do it from the beginning right to the very end.
Full of beans
If someone's full of beans, they are very energetic.
Glutton for punishment
If a person is described as a glutton for punishment, he happily accepts jobs and tasks that most people would try to get out of.
Go fry an egg
(USA) This is used to tell someone to go away and leave you alone.
Gone pear-shaped
(UK) If things have gone pear-shaped they have either gone wrong or produced an unexpected and unwanted result.
Good egg
A person who can be relied on is a good egg. Bad egg is the opposite.
Grain of salt
If you should take something with a grain of salt, you shouldn't accept it as true without looking more carefully at it. ('pinch of salt' is an alternative)
Gravy train
If someone is on the gravy train, they have found and easy way to make lots of money.