1. Preheat the oven to 190ºC (190 degrees C).
2. Place the butter or margarine in a heatproof glass dish. Cover and microwave on high power for 30 seconds.
3. In a large bowl,mix together pumpkin, sugar, melted butter or margarine, beaten egg, milk and vanilla extract.
4. In a separate bowl, combine the flour, baking powder, baking soda, cinamon and salt. Add to the pumpkin mixture, and mix until smooth.
5. Stir in the chocolate chips and, if you wish, nuts.
6. Drop from a teaspoon onto a lightly greased baking sheet. Line up about 4 cm apart.
7. Bake for ten to dozen minutes, until golden brown.
8. Cool on baking sheet for two minutes or so. Then remove to a wire rack to finish cooking.
9. Now you have about three dozen pumpkin cookies for Halloween!