1Preheat your oven to 350°F (175°C).
In a large bowl, cream together the margarine and sugar until smooth.
Beat in the egg and evaporated milk until well combined.
In a separate bowl, whisk together the flour, cocoa powder, and oats.
Gradually add the dry ingredients to the wet ingredients, mixing until just combined.
Drop spoonfuls of dough onto a greased baking sheet, spacing them about 2 inches apart.
Bake for 10-12 minutes, or until the edges are set and the centers are still slightly soft.
Allow the cookies to cool on the baking sheet for a few minutes before transferring them to a wire rack to cool completely.