In a large bowl, whisk together the flour, rolled oats, baking soda, baking powder, salt, cinnamon, and black pepper. Set aside.

In a stand mixer fitted with the paddle attachment, cream the butter, brown and granulated sugars, and vanilla on medium speed until light and fluffy, about 3 minutes.

Add the eggs, one at a time, beating on medium speed until incorporated. Add the flour mixture all at once and mix until just incorporated. Mix in the raisins and coconut flakes. You may need to give the bowl a couple of swipes with a rubber spatula at the end to make sure the ingredients are evenly distributed.

Line a baking sheet with parchment paper. Scoop the cookie dough using a #16 (¼-cup) portion scoop onto the baking sheet. You can make the cookies larger or smaller, but it will affect the baking time.

Refrigerate the dough balls for at least 30 minutes; if you have the time, they improve if you let them sit for 24 to 36 hours. After they are chilled, you can bake them or freeze the dough balls for baking later.

Preheat the oven to 350°F / 175°C, with racks in the top and bottom thirds of the oven.

Evenly space six chilled cookies on each sheet. Bake in the oven with one sheet on the top rack and the other on the bottom rack for about 12 minutes. Rotate the baking sheets top to bottom and continue baking for about 5 more minutes, or until golden brown on top.

Allow the cookies to cool for a few minutes on the baking sheets and then move to a cooling rack.