Preheat oven to 400°F and line twelve muffin cups with paper liners.
In a largish bowl, stir together the flour, sugar, baking powder, cinnamon and salt. In a smaller bowl (or Pyrex measuring cup) stir together the milk, oil and egg, and add it to the flour along with the mincemeat. Stir until the batter is almost combined, then add the apple and nuts and stir just until blended. Don't worry about getting the lumps out.
Fill the muffin cups almost full and bake for 25 minutes, or until golden and springy to the touch. Serve warm.