Begin by describing one or more than one of the restaurants in Harlem. Include a bevy of sensory details (this is a piece about food, after all). Discuss the colors, scents, the particular types of food being served to people (meats, vegetables, etc.) Also focus briefly on the customer base, note its diversity, add this to the sensory details where possible (for example the click of the utensils as a Russian company enjoys the ambiance of the restaurant, etcetera). The key is to show, don't tell. You don't want the reader to know what you're talking about in the first few paragraphs.
Delivery of the Who, Where, What, Why, How, etcetera
Explain that the aforementioned details can be seen taking place at any variety of African restaurants in Harlem. Denote the vast influx of such restaurants in the past couple of years, including all the ones you named in the instructions, the years they opened, as well as the particular cultures they represent. Be sure to mention those that are set to open and the multi-owners. This is the key part in the article that you truly want to hype up the fact that this is a PHENOMENON that your reader needs to care about.
III. Transition to the Core of the Article
B. Explicate that this is a fairly recent phenomenon, and go a little into the history of it. Allude to the secret beginnings of this cuisine in the SRO hotel rooms, also provide the contextual evidence of the broader Harlem revival that this is a part of. Imply that this latter fact is possibly intertwined with the growing movement to this type of cuisine. Explain the article will identify the factors that account for this phenomenon.
IV. Case Study: The Senegalese Chef at Ponty Bistro