Lay a 3-foot piece of waxed paper on a cookie sheet.
A a medium bowl, stir the sugar and cocoa together.
Melt the butter in a 4-quart pan. Add milk and sugar/cocoa mix. Stirring constantly, bring to a boil, and let boil for 1 minute.
Remove from heat and add the vanilla and rolled oats. ½ cup peanut butter can be added to make smoother.
Drop one cookie by the spoonful onto the wax paper to see if there is any liquid that spreads from the cookie. If there is, add another ¼ cup of rolled oats at a time until no liquid runs from cookie.
Let cookies set (may need to put in refrigerator). Store in an air tight container.