Lightly grease a cookie sheet or parchment paper. They do not work on a Silpat type pad.
Mix the egg replacer and set aside.
Melt chocolate over a double boiler.
Meanwhile, add the sugar to the butter in a medium bowl. Beat at medium speed with a hand mixer until it is light and fluffy.
To the sugar mixture add the egg replacer mix, vanilla extract and melted chocolate.
Add flour and baking powder and mix on low speed.
Stir in oatmeal by hand. Chill for 30 minutes.
Roll cookie dough into about ¾" balls.
Place far apart (by at least 2") on the cookie sheet. The cookies really spread out.
Bake at 350° for 8 minutes.
Let cool for just a minute or so and then use a spatula to put on a wire rack to cool.
Store in a tightly closed container.