Preheat the oven to 400 degrees. Liberally butter a 9x13 pan and set aside.
In a large mixing bowl, stir together the flour, sugar, baking powder, and salt. Using a pastry blender or fork, cut in the butter. Add the egg, milk, and vanilla and beat at medium speed with an electric mixer just until well blended. Reserve 1/2 of the batter for topping and set it aside for now.
Spread the remaining batter in the buttered baking pan. In a small bowl (or the measuring cup), stir the raspberry preserves to loosen them a bit. Dollop the preserves over the batter, then spread them evenly. Sprinkle the chocolate chunks evenly over the preserves. Drop the reserved dough by spoonfuls over the chips.
Bake 20-25 minutes or until the batter is golden brown. Remove from the oven and cool completely on a wire rack. Cut into bars. When ready to serve, dust with confectioner’s sugar.