Add eggs to a large mixing bowl. Using a whisk or an electric mixer, beat well. Add the oil, granulated sugar, and vanilla. Beat until completely combined.
Next, add the cocoa powder, salt, baking powder, and flour. Mix until well combined.
Refrigerate dough for at least 2 hours or overnight.
Time to bake
Pre-heat oven to 350 degrees.
Line a cookie sheet with parchment paper or foil.
Using spoons or a cookie scoop, form dough into 1 to 1 ½ inch balls. Thoroughly roll into powdered sugar and place on the cookie sheet at least 2 inches apart.
Bake the cookies for 10 - 12 minutes. Do not over bake.
Let the cookies cool for a minute or two on the cookie sheet and then move them to a cooling rack. Cool another 2 to 3 minutes and slightly press a Hershey Kiss into the center of the cookie.