Preheat oven to 350 degrees. Line a baking sheet with parchment paper or Silpat.
In a medium bowl, whisk together flour, baking soda, spices, and salt. Set aside.
In the bowl of a stand mixer or a separate bowl using a hand mixer, combine brown sugar, molasses, and vegetable oil. Mix on medium speed until thoroughly combined; about 3 minutes. Scrape down the bowl (this ultra-thick mixture will stick tenaciously, so you might have to put some muscle into it), and mix in the first egg, then the second. Beat about a minute longer, until the batter is smooth and uniform.
Add the flour mixture on low speed until all traces of flour have disappeared and the dough begins to clump together. Stir in crystallized ginger, if using.
Using a medium cookie scoop or a spoon, scoop dough into 1.5-inch balls. Dip each in granulated or ginger sugar. Place cookies 2 inches apart on prepared baking sheet and flatten slightly.
Bake at 350 degrees for 12 mins. These cookies don’t brown much so be sure not to overbake, which will render them dry and crumbly.
