This is lifted from Epicurious.com who lifted it from The Bump and Grind Cafe in Denver. This is how I do them, and since most of my recipes are here, it makes MY life easier to post it. BTW you will want to double this recipe.
Using a mixer, cream the butter with the sugar, add the orange peel, extract, egg yolk and whipping cream. The room temperature ingredients are key so that you can create a smooth, homogeneous mix.
Stir the dry ingredients into the wet, mixing *just* until it is incorporated.
Stir in the chocolate chips.
This is a pretty dry dough, so blend it with a wooden spoon to incorporate the dry bits and break up any concentrations of chocolate chips.
At this point you can make about 1" balls of cookie dough that you can then press out on a cookies sheet covered with parchment paper. These cookies don't spread much when baking.
Bake approximately 7-10 minutes rotating the pan during cooking as needed.
Alternatively, you can take the whole of the cookie dough and roll it into a log, wrap it in plastic wrap, then refrigerate until firm. Next you can slice off about 1/4" cookies. This latter option makes for a more uniform cookie and a smoother appearance.
Note: if you use a whole egg instead of just the egg yolk, the cookies bubble up a bit and have a lumpy appearance. Still tasty, though.