Preheat the oven to 425°F. Grease a 9-inch-round baking pan with spray oil and set aside. (Note: These do not bake as well in disposable aluminum pans.)
Place 2 cups of the flour, the sugar, baking powder, and salt into the bowl of a food processor fitted with a metal blade. Pulse for 10 seconds. Cut the butter or chilled margarine into small pieces and scatter over the dry ingredients. Mix for about 10 seconds, or until mixture resembles sand. You can also cut the fat into the dry ingredients by hand.
Beat 1 egg and add it and the milk to the flour and fat mixture. Process or mix just until the dough starts to come together, about 5 seconds. Sprinkle 1 tablespoon of flour on the counter. Place the dough on the floured counter and knead gently into the flour until the dough is smooth. Add a little more flour if the dough seems sticky and knead it in. Divide the dough in half.
Shape one-half of the dough into a ball and place on parchment sprinkled with flour. Use a rolling pin to roll into a pancake the size of your baking pan. Place the dough into the pan. With a sharp knife dipped in flour, score (mark, but do not cut completely through) the top of the dough into 8 wedges.
Place a 3 x 3/4-inch bar of chocolate into each triangle and press it into the dough. You can also use any smaller or broken pieces; just place them in the shape of a bar in each triangle.
Take the other half of the dough and roll out into a second large pancake, as you did with the first half, and place on top of the chocolate bars.
Use your fingers to press the dough between the bars and around the edges to completely cover the chocolate bars with the dough.
Take your knife and score again into 8 triangles around the chocolate pieces. Beat the remaining egg and brush the top of the dough. Bake for 15 to 20 minutes, or until the top is brown. Let cool for 10 minutes and then remove from the pan. Cut on the scored lines into wedges. Serve warm or at room temperature.