Oatmeal Breakfast Cookies

So I've been researching breakfast cookies for a while. I knew that they would be an easy sell for the kiddos. A cookie for breakfast? They thought they had died and gone to heaven. I kind of mixed up a whole lot of recipes and added a few things of my own.

These taste great. But I need someone to explain the science to me about why the batter when contacted with air the batter started to turn green. The first batch turned out with just a green tint (pictured). The second set of cookies to go in were quite green from the sitting out in the air for 20 minutes while the first set baked. They taste completely fine and no one is sick, but something about the combination is making a green color. Maybe a fit for Christmas or St. Patty's???

1/2 c Sunbutter butter (or any nut butter)
1/2 c Applesauce
1/2 c Brown sugar, packed
1 Egg (or 3 T water/1 T flax meal mixed)
1 t Vanilla
2 ripe Bananas, mashed
1/2 t Baking soda
1/2 t Salt
2 c Flour (or Carol Fenster GF mix)
1 T Flaxseed, ground
2 c Old Fashioned oats*
1 c Dried fruit or chocolate chips

* I only have GF rolled outs so I pre-moistened them with about 1/2 c of apple juice and stirred it until the juice was absorbed.

Beat the sunbutter and applesauce until combined. Beat in the brown sugar, egg, and vanilla. Add in the bananas, baking soda, and salt. Add the flour and ground flaxseed, mixing until combined. Stir in the oatmeal and raisins/chips.

Drop 1/4 cup dollops of batter four inches apart onto parchment paper. Bake for 15-18 minutes at 350. Let stand 1 minute on the tray, then remove to a wire rack.