If your chocolate looks gritty, crumbly, and anything but smooth, it's seized. This happens when water gets into your melted chocolate. Here's how you can fix seized chocolate: Add boiling water (it seems counterintuitive, I know) 1 teaspoon at a time, stirring very well after each addition, until the chocolate is smooth again. This will end up diluting your chocolate, so you will want to keep this in mind depending on how you plan to use it. Personally, I usually just start over if my chocolate becomes seized.