Easy Chocolate Sauce

Sometimes I like to make a chocolate sauce that is rich tasting but does not involve melting chocolate because either I don't have the chocolate or I don't feel like chopping chocolate and would rather make something easy without foregoing taste.  This recipe is easily made with pantry staples - sugar, cocoa, and evaporated milk.  It is best used within the week it is made as the sugar becomes granular after a few reheats.  Also, it does not harden with the cold from the ice cream like a ganache does.  
This recipe is from my sister-in-law who uses it as frosting on spice cake, her kids favorite birthday dessert.

Easy Chocolate Sauce
makes 1 cup

1 cup sugar

5 tablespoons cocoa

2 tablespoons butter

1 small can (5 ounces) or 5/8 cup evaporated milk

1 teaspoon vanilla

Stir sugar and cocoa over low heat for 30 seconds – do not let sugar melt.

Blend in butter.

Add evaporated milk, stirring constantly.

Turn heat to medium and bring to boil stirring constantly.

Boil for 1 minute.

Remove from heat and add vanilla.