Combine the butter and shortening in a bowl and beat for a few seconds. Add the
sugar and beat until creamy. Add the egg, dry milk and vanilla extract and beat
light until light.
Combine the flour, baking soda and salt in a bowl. Stir with a fork to mix and
lighten. Add to the butter mixture and blend well. Stir in the pecans and mix well.
Drop heaping tablespoons of dough 2 inches apart onto the baking sheet. Dip the
bottom of a 3-inch diameter drinking class into flour and use it to press the dough
into a circle of the same dimension. If the dough sticks a little as you lift off
the glass, scrape it from the glass and pat any bits back into the circle of dough
to make it even and neatly round. Dip the glass into flour after each use.
Bake the cookies for 7 to 10 minutes, or until golden brown.
Remove from the
oven and gently lift the cookies onto a cooling rack. Let cool completely, then
store in an airtight container.