Preheat your oven to 350°F and position a rack in the middle. Line baking sheets with parchment paper.
In a medium bowl, whisk together the flours, oats, pecans, and cranberries.
Using a stand mixer, cream the butter, sugars, salt, baking soda, cinnamon, and vanilla extract on low speed until combined, then increase to medium and mix for about 30 seconds.
Add the egg and mix until smooth. Gradually incorporate the dry ingredients until a stiff dough forms.
Portion out 2-tablespoon-sized scoops of dough, placing them 2 inches apart on the baking sheets. Flatten each scoop to about 1/2-inch thick discs.
Bake for 12 minutes, until the edges are lightly golden but the centers remain soft. Cool cookies on the baking sheet for 5 minutes before transferring to a wire rack.
Store in an airtight container at room temperature for up to 2 days.