Preheat oven to 350°F. Grease a 9-inch loaf pan and set aside.
Stir together flour, sugar, baking powder, baking soda and salt in a large bowl. Add in crushed pineapple with the juices, egg and oil. Stir. Add cheddar cheese and walnuts and stir. Pour into loaf pan. Let rest for 20 minutes.
Bake for 1 hour or until a toothpick comes out of the centre clean. Let cool before cutting into slices. Makes 1 loaf.