For Skillet Cookies:
1. Preheat oven to 350°F. Place a saucepan filled halfway with water over medium heat. Place a bowl on top of saucepan. Place butter and chocolate in bowl, and melt over saucepan of boiling water, stirring constantly. Alternatively, combine butter and chocolate in a bowl, cover with plastic wrap and microwave 1 minute stirring until melted. Cool slightly.
2. In a mixing bowl with beaters, whisk eggs and sugar together until light and fluffy. Add cooled chocolate mixture, beating well.
3. Combine flour, baking powder, and salt. Whisk flour mixture into cooled chocolate mixture. Dough should be light and fluffy. Cover securely and chill at least 2 hours or as long as 1 day.
4. After cookie dough sits in the refrigerator for at least 2 hours, scoop 4 golf-ball-sized spoonfuls of dough into a lightly greased or well- seasoned 6-inch iron skillet. Press cookie dough scoops together to a 3/4 to 1-inch depth. Bake 5 minutes; check each minute as you bake longer, no longer than 6-8 minutes. Do not over-bake. Edges should look baked and center should look moist and shiny when done.
For Traditional Cookies:
1. Preheat oven to 350°F and line baking sheets with parchment paper. Prepare cookie dough as above except using chopped chocolate. Using a small ice cream scoop or spoon, scoop and roll dough into a loose ball (golf ball size) and place at least 2 inches apart on cookie sheet. Press each to flatten slightly. Bake 5 minutes then remove from oven and sprinkle with sugar. Bake 1-2 more minutes. Do not over-bake. Cookies should still look moist on top. Remove from oven, cool, and store in a tightly closed container. Yields 32 cookies.