Preheat the oven to 350 degrees Fahrenheit (180 degrees Celsius).

Combine flour, salt, baking powder, cinnamon, ginger, and sesame seeds, if using, in a small bowl, and set aside.

Mix the melted margarine and rolled oats very well in a medium-sized bowl and set aside.

Cream the egg and sugar in the bowl of your mixer. Add the flour mixture. Don’t overmix.

Add the oats and margarine, and mix gently until it comes together as one dough.

Using a spoon, scoop dough into balls one and a half inches in diameter and place on a lined baking sheet, leaving room for expansion. Bake for 8–10 minutes just until the cookies turn slightly golden. Be careful not to burn.

Let cool and store in a tightly sealed container. If desired, melt white chocolate in a double boiler and drizzle on top of each cookie.