According to the US Customs and Border Protection Prohibited and Restricted Items page,
Food Products (Prepared)
You may bring bakery items and certain cheeses into the United States. The APHIS Web site features a Travelers Tips section and Game and Hunting Trophies section that offers extensive information about bringing food and other products into the U.S. Many prepared foods are admissible. However, bush meat made from African wildlife and almost anything containing meat products, such as bouillon, soup mixes, etc., is not admissible. As a general rule, condiments, vinegars, oils, packaged spices, honey, coffee and tea are admissible. Because rice can often harbor insects, it is best to avoid bringing it into the United States. Some imported foods are also subject to requirements of the U.S. Food and Drug Administration.
Prior Notice for Food Importation
The Public Health Security and Bioterrorism Preparedness and Response Act of 2002 (Bioterrorism Act or BTA), Public Law 107-188, established the requirement that food items, imported (or offered for import) for commercial use, including hand-carried quantities, be properly reported to the U.S. Food and Drug Administration prior to arrival of those items in the United States. The FDA prior notification timeframes (by transport mode) are two hours by land, four hours by rail or air, eight hours by vessel and prior to the "time of mailing" for international mail.
Food that was made by an individual in his/her personal residence, or food purchased by an individual from a vendor that is sent by that individual as a personal gift (for non-business reasons) to someone in the United States is not subject to Bioterrorism Act requirements. However, food that is sent to an individual in the United States by a business is subject to special requirements of the U.S. Food and Drug Administration. For instance, if you go to a food shop in England and buy a gift basket, then take it to the post office or a courier service to send to a friend, the shipment is not subject to BTA requirements. But if you go to that same shop and ask them to send the gift basket for you, the shipment is subject to BTA requirements, and the vendor will have to file Prior Notice. Many travelers are finding that vendors will not ship food directly to U.S. residents because the reporting requirements can be time-consuming to complete.
In general, failure to provide complete, timely and accurate prior notice for Bioterrorism Act regulated items, can result in refusal of admission of the merchandise, movement of the goods to an FDA registered facility (at importer expense) and/or civil monetary penalty liabilities for any party that was involved in the import transaction.
For full details regarding the latest FDA requirements, including those food items exempt from these requirements, access the FDA's Counterterrorism-Related Legislation page.
Fruits and Vegetables
Bringing fruits and vegetables depends on a number of factors. For instance, consider the apple you bought in the foreign airport just before boarding and then did not eat. Whether or not CBP will allow the apple into the United States depends on where you got it and where you are going after you arrive in the United States. The same would be true for Mediterranean tomatoes. Such factors are important because fresh fruits and vegetables can introduce plant pests or diseases into the United States.
One good example of problems imported fruits and vegetables can cause is the Mediterranean fruit fly outbreak during the 1980s. The outbreak cost the state of California and the federal government approximately $100 million to get rid of this pest. The cause of the outbreak was one traveler who brought home one contaminated piece of fruit. It is best not to bring fresh fruits or vegetables into the United States. However, if you plan to, contact either CBP or check the Permits section on the USDA-APHIS Web site for a general approved list on items that need a permit.
Note: The civil penalty for failing to declare agricultural items at U.S. ports of entry will cost first time offenders $300. The penalty for the second violation goes up to $500. To avoid receiving a penalthy all agricultural items and present them to Customs and Border Protection for inspection so that an agriculture specialist can determine if it is admissible.
I would, however, strongly suggest you read the whole page in case it changes between now and your date of travel, and in case any of the other paragraphs also apply to you depending on what you intend to bring.
In addition, the page that @pnuts linked, Travelers bringing food into the U.S., is also a good resource.