Combine first 4 ingredients in a medium bowl. Spread evenly into an 8-inch square baking dish coated with cooking spray. Bake at 350° for 30 minutes or until edges are lightly browned and center is almost set. Cool on a wire rack.
Cut pudding into 12 equal portions. Pour milk over pudding. Cover and refrigerate 8 hours or overnight. Sprinkle cardamom over pudding. Spoon 1 serving pudding and about 2 teaspoons milk into each of 12 small bowls, and top each serving with 1 teaspoon pistachios.
This was a disaster for us. After almost twice the baking time the pudding still wasn't set but the edges were getting dark so I had to take it out. It was just a gloppy soupy mess. Not sure what went wrong - but I tasted the soupy mess and it was delicious! Just not in an edible form, unfortunately...