Preheat oven to 325º. Line cookie sheets with parchment paper.
In a small bowl, whisk flour, cocoa, baking soda and salt. Set aside.
In a stand mixer, combine oil, brown sugar and white sugar and mix until smooth. Add eggs and mix until creamy. Mix in red food coloring, vanilla and vinegar. Add flour mixture until completely combined.
Using small cookie scoop, scoop dough into about 1" balls. Roll in your hands and place on cookie sheet; 12 cookies per sheet.
Bake for about 12 minutes in preheated oven, or until edges are set. Remove from oven and press Hershey's Kiss candy into the middle of each cookie. Let rest for one minute and then gently tap the cookie sheet on counter to make the Kiss drop into a thumbprint. Alternately, if you'd like the Kiss intact, don't tap the cookie sheet. They both look cute! Move to cooling rack and enjoy!