In a large bowl, cream together the shortening and brown and granulated sugars. Add the egg yolk and vanilla extract, and mix until completely incorporated. Gradually add the flour and salt, and mix until completely incorporated. Add the mini chocolate chips, and mix together until evenly distributed. The dough should be a little crumbly at this point.
Melt chocolate candy melts, and then pour the melted chocolate into the well of each cookie. Let it sit for a minute, and then pour the excess chocolate back into the pan. Chill cookie shots until the chocolate has set.