I find that this recipe impresses people. Maybe they figure that chocolate syrup is made in a factory and bottled, I am not sure but people are always surprised when I tell them I make my own chocolate syrup for a fraction of the cost of the store bought kind and is really easy. Funny thing is that I found the recipe on the side of a can of store bought cocoa.
In a saucepan combine:
1 cup cocoa
1 1/2 cups sugar
1/2 tsp salt
1 1/2 cups water
Bring to a boil and simmer for 5 minutes stirring constantly
store in an air tight container in the fridge. Mine always gets eaten in about 3 weeks to a month so I am not sure how long this keeps for but I would guess quite a while because it's only cocoa/sugar water.
I also store mine in an old chocolate syrup container I had left over from when I used to buy it. I wash it between batches though so it doesn't get crusty but you can keep it in any air tight container.
Use this as you would store bought syrup. I like to pour the fresh warm syrup on ice cream, put a little in my coffee, iced coffee or frappuccino, and even make chocolate milk and soy milks with it.