Food-related idioms

Beef up   

If you “beef up” something, you improve it or make it stronger.  For example, to “beef up” your paper, your professor may mean that you need to do more research, cite more examples, or write more about each point you make. But, to be sure, you’d ask him how he thinks you should “beef up” your paper.  
 
Here’s how you might use this expression: “Even with the “No Child Left Behind” program, U.S. public schools aren’t performing as they should. As a result, American children aren’t competitive with their peers from other countries. I hope the Obama administration will beef up public schools’ math and science programs.” 
 
Beefing up and eating a juicy Big Mac have nothing to do with each other. 

Food for thought  

If someone gives you “food for thought,” that person is providing an idea or concept that you can ponder or think about further.  In other words, his comments are a stimulus or catalyst to thinking more deeply about an issue or topic.  
 
Here’s an example of how to use this phrase: “Because there were many out-of-work professionals at the meeting, the speaker decided to discuss how they could reposition themselves in a difficult economy. By doing so, the speaker provided the attendees with food for thought on their career reinventions.” 
 
When you tell someone that he provided “food for thought,” most likely, you’re complimenting that individual. 

Have bigger fish to fry    

If you need to get something done—like a term paper or project at work—and someone asks you to go shopping with them, you might reply that you can’t do so because you have more important things to do. Another way of declining this invitation is to say, “I can’t go shopping with you because I “have bigger fish to fry.” 
 
Have you recently had to give up doing something you enjoy because you had bigger fish to fry?

Soup to nuts       
This expression means from the start of something to its end. Wikipedia says that this rather strange term is derived from the description of a multi-course dinner, which starts with soup and finishes with a dessert that includes nuts. Of course, nowadays, most people are too busy to eat that many courses.

Here’s how you might use this phrase: “Jing, you need to plan your wedding. But, because you’re extremely busy at work, you should hire a wedding planner. Event planners can make your life much easier. They deal with everything and everyone—from soup to nuts. That way, you can focus on your job.”

The best thing since sliced bread      

The phrase “the best thing since sliced bread” relates to the American innovation of pre-sliced and packaged bread. Wonder Bread, the first mass marketer of this product, used this (or a similar) phrase in a 1930s ad campaign. This phrase means that an innovation or other development is excellent. 
 
Here’s how to use this expression: “Ping, I really appreciate your introducing your friends to me. They’re helping me tremendously. In fact, collectively, they’re the best thing since sliced bread.” 
 
The next time someone uses this phrase and compares you to “bread,” you’ll know that it’s a compliment.