To make a chocolate glaze or icing that hardens when cool you need 2 tablespoons of melted margarine or oil, 2 tablespoons unsweetened cocoa, 2 tablespoons hot water, 1 cup confectioner's sugar, and 1/2 teaspoon vanilla. Mix your margarine, cocoa, and hot water in a bowl. Add in the sugar and vanilla and mix well. You can then pour it or spread onto your cakes, brownies, cookies, or other dessert. Let sit until hardened before cutting.