Preheat oven to 350°F. Line a cookie sheet with parchment paper.

Add the egg and milk to a small mixing bowl and whisk together. Put aside until use.

Cut the dark chocolate into chunks.

Prepare a medium mixing bowl and a stick mixer with blade inserts.

Sift the flour and baking powder into the mixing bowl. Add the sugar.

Cut the butter into squares and add to the bowl. Add the chunky peanut butter.

Using the stick mixer, mix to a texture of coarse crumbs (if you don't have a machine, you can use your fingertips).

Move the mixture to a large mixing bowl. Pour the egg & milk solution into the dry mixture and use a rubber spatula to mix until half mixed.

Add the chocolate chunks to the mixture and mix well (Be careful not to mix too much).

Place the mixture on a lightly floured surface. Roll out the dough to about 2cm thickness. Cut out the biscuits with a round cookie cutter.

Place on prepared cookie sheet. Bake for 18 minutes or until the tops are slightly brown. Remove from oven and place on a wire rack.

More Details at http://www.chez-k.org/english/hot-biscuits/peanut-butter-choco-chunk/