Preheat oven to 350 F. Grease muffin tins, or use paper cups in muffin tins.
In a small bowl, combine banana flake powder and water until smooth.
In a large bowl, blend sugar, egg, oil and vanilla. Add the banana flake mixture.
In a medium bowl, blend flour, baking soda, nutmeg and salt. Stir into
banana mixture just until combined. Stir in yogurt and walnuts; do not
over-mix. Pour 1/3 cup batter into prepared muffin tins.
Bake for 18-22 minutes until golden brown.
Makes 12 muffins.