I thought these cookies were heaven. I added white chocolate chips instead of chunks and they seemed a little too sweet. I, however, was willing to overlook it. Unfortunately, we ended up throwing most of them away because #3 was born the day after I made them, and they sat on the counter untouched for a week.
Do not bake the cookies to a crisp; they are meant to be soft and chewy. Store them in an airtight container at room temperature for two to three days.
From Martha Stewart’s website. 
4 T unsalted butter
2/3 c all-purpose flour
1/2 t baking powder
1/2 t salt
2 large eggs
3/4 c packed light-brown sugar
1 t vanilla extract
1 package (12 oz) semisweet chocolate chunks
Preheat oven to 350 degrees. Heat chopped chocolate and butter in a microwave-safe bowl in 20-second increments, stirring in between, until almost melted; do not overheat. In another bowl, whisk together flour, baking powder, and salt.
In a mixing bowl, beat eggs, brown sugar, and vanilla on high speed until light and fluffy. Reduce speed to low; beat in melted chocolate. Mix in flour mixture until just combined. Stir in chocolate chunks.
Drop heaping tablespoons of dough 2 to 3 inches apart onto baking sheets. Bake, rotating sheets halfway through, until cookies are shiny and crackly yet soft in centers, 12 to 15 minutes. Cool on sheets 10 minutes; with a thin metal spatula, transfer to racks to cool completely.
