1. 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.
2. 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.
3. 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.
