First some note on the ingredients. The oatmeal should be run though a blender until it is very fine. The chocolate bar that you need to grate is the kind you buy to eat on the way home from the grocery store, use your favorite, but you will need to buy a pretty big one. Chocolate also grates easier if it is nice and cold.
For the recipe, start out by creaming the butter and lard (you can vary the ratio of these a little) with the sugars. Add in the eggs and vanilla. Combine the flour, baking soda, salt, baking powder, and oatmeal, then mix it into the batter.
Thoroughly mix in the grated chocolate bar, then add in the chocolate chips (and nuts if you like.)
Bake as usual, at about 375 degrees for roughly 10 minutes depending on the size of your cookies.