Beat the egg, vanilla extract and sugar in a bowl. Add oil and mix well. Set the egg mixture aside.

In a large bowl, combine oatmeal, flour, baking soda, cinnamon and salt.

Add in the egg mixture to the dry ingredients and combine well. Fold in the chocolate chips.

Cover the dough tightly and chill the dough for 30 minutes to an hour.

Preheat oven to 350 degrees F. Line a cookie sheet with parchment paper.

Using a cookie scoop, scoop out balls of the dough onto the cookie sheet, about 2 inches apart.

Bake for 12-14 minutes or until they have just started to brown on the edges.

Remove from oven and let cool on the baking sheet for about 10 minutes and then place on a wire rack to cool completely.